implement stacey boundary condition for couple_with_injection on GPU, add

EXAMPLES/applications/small_example_coupling_FK_specfem_with_fluid/DATA/CMTSOLUTION

@@ -0,0 +1,13 @@
+XXXX2011 11 11 11 11 11 11  11 11     11.1111 111.1 1.1 1.1 EVENT1 EVENT111
+event name:     SYNTHEVENT001
+time shift:      0.0
+half duration:   0.1
+latitude:        2000.0
+longitude:     200.0
+depth:         -10.0
+Mrr:       1e23
+Mtt:       1e23
+Mpp:       1e23
+Mrt:       0
+Mrp:       0
+Mtp:       0

EXAMPLES/applications/small_example_coupling_FK_specfem_with_fluid/DATA/FKMODEL

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+# 
+#  input file for embedded FK modeiling 
+#
+#  for each layer we give : 
+#  LAYER ilayer rho vp vs ztop
+#  the last layer is the homogeneous half space 
+#
+#
+# model description  ---------------------
+NLAYER             5
+LAYER 1 1000. 1500. 0.     0.
+LAYER 2 2720. 5800. 3460.     -5000. 
+LAYER 3 2920. 6500. 3850. -20000.
+LAYER 4 3423. 8060. 4530. -35000.
+LAYER 5 3423. 8289. 4517. -120000.
+#----------------------------------------
+# incident wave p or sv 
+INCIDENT_WAVE      p
+#----------------------------------------
+# anlges of incomming wave
+BACK_AZIMUTH           68.
+TAKE_OFF               20.
+#----------------------------------------
+FREQUENCY_MAX      0.25
+#----------------------------------------
+TIME_WINDOW       100.
+#----------------------------------------
+# optional 
+#ORIGIN_WAVEFRONT  1. 2. 3.
+#ORIGIN_TIME 0.

EXAMPLES/applications/small_example_coupling_FK_specfem_with_fluid/DATA/STATIONS

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+STA0001 XX 0. -100000.000000 0.  -4000
+STA0002 XX 0. -68750.000000 0.  -4000
+STA0003 XX 0. -37500.000000 0.  -4000
+STA0004 XX 0. -6250.000000 0.   -4000
+STA0005 XX 0. 25000.000000 0.   -4000
+STA0006 XX 0. 56250.000000 0.   -4000
+STA0007 XX 0. 87500.000000 0.  -4000
+STA0008 XX 0. 118750.000000 0. -4000
+STA0009 XX 0. 150000.000000 0. -4000
+STA0010 XX 0. 25000.000000 0.   -4999.9
+STA0011 XX 0. 25000.000000 0.   -5000.1

EXAMPLES/applications/small_example_coupling_FK_specfem_with_fluid/DATA/meshfem3D_files/Mesh_Par_file

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+#-----------------------------------------------------------
+#
+# Meshing input parameters
+#
+#-----------------------------------------------------------
+
+# coordinates of mesh block in latitude/longitude and depth in km
+LATITUDE_MIN                    = -150000.0
+LATITUDE_MAX                    = 150000.0
+LONGITUDE_MIN                   = -150000.0
+LONGITUDE_MAX                   = 200000.0
+DEPTH_BLOCK_KM                  = 250.0
+UTM_PROJECTION_ZONE             = 11
+SUPPRESS_UTM_PROJECTION         = .true.
+
+# file that contains the interfaces of the model / mesh
+INTERFACES_FILE                 = interfaces.dat
+
+# file that contains the cavity
+CAVITY_FILE                     = no_cavity.dat
+
+# number of elements at the surface along edges of the mesh at the surface
+# (must be 8 * multiple of NPROC below if mesh is not regular and contains mesh doublings)
+# (must be multiple of NPROC below if mesh is regular)
+NEX_XI                          = 16
+NEX_ETA                         = 16
+
+# number of MPI processors along xi and eta (can be different)
+NPROC_XI                        = 2
+NPROC_ETA                       = 2
+
+#-----------------------------------------------------------
+#
+# Doubling layers
+#
+#-----------------------------------------------------------
+
+# Regular/irregular mesh
+USE_REGULAR_MESH                = .true.
+# Only for irregular meshes, number of doubling layers and their position
+NDOUBLINGS                      = 0
+# NZ_DOUBLING_1 is the parameter to set up if there is only one doubling layer
+# (more doubling entries can be added if needed to match NDOUBLINGS value)
+NZ_DOUBLING_1                   = 11
+NZ_DOUBLING_2                   = 0
+
+#-----------------------------------------------------------
+#
+# Visualization
+#
+#-----------------------------------------------------------
+
+# create mesh files for visualisation or further checking
+CREATE_ABAQUS_FILES             = .false.
+CREATE_DX_FILES                 = .false.
+CREATE_VTK_FILES                = .true.
+
+# stores mesh files as cubit-exported files into directory MESH/ (for single process run)
+SAVE_MESH_AS_CUBIT              = .false.
+
+# path to store the databases files
+LOCAL_PATH                      = ./DATABASES_MPI
+
+#-----------------------------------------------------------
+#
+# CPML
+#
+#-----------------------------------------------------------
+
+# CPML perfectly matched absorbing layers
+THICKNESS_OF_X_PML              = 12.3
+THICKNESS_OF_Y_PML              = 12.3
+THICKNESS_OF_Z_PML              = 12.3
+
+#-----------------------------------------------------------
+#
+# Domain materials
+#
+#-----------------------------------------------------------
+
+# number of materials
+NMATERIALS                      = 5
+# define the different materials in the model as:
+# #material_id  #rho  #vp  #vs  #Q_Kappa  #Q_mu  #anisotropy_flag  #domain_id
+#     Q_Kappa          : Q_Kappa attenuation quality factor
+#     Q_mu             : Q_mu attenuation quality factor
+#     anisotropy_flag  : 0 = no anisotropy / 1,2,... check the implementation in file aniso_model.f90
+#     domain_id        : 1 = acoustic / 2 = elastic
+1  2720  5800  3460  9999. 9999.  0  2
+2  2920  6500  3850  9999. 9999.  0  2
+3  3423  8060  4530  9999. 9999.  0  2
+4  3423  8289  4517  9999. 9999.  0  2
+5  1000  1500   0.   9999. 9999. 0   1
+
+#-----------------------------------------------------------
+#
+# Domain regions
+#
+#-----------------------------------------------------------
+
+# number of regions
+NREGIONS                        = 5
+# define the different regions of the model as :
+#NEX_XI_BEGIN  #NEX_XI_END  #NEX_ETA_BEGIN  #NEX_ETA_END  #NZ_BEGIN #NZ_END  #material_id
+1            16              1             16            50            50          5
+1            16              1             16            47            49          1
+1            16              1             16            44            46          2
+1            16              1             16            27            43          3
+1            16              1             16            1            26          4
+