add dimer and liquid boxes for TIP4P and OPC water

Author: jayponder

example/opc.key

@@ -18,20 +18,17 @@ dielectric              1.0000
 ## OPC Parameters (J Phys Chem Lett, 5, 3863-3871, 2014)
 
 atom             1    O     "OPC Water O"     8      15.995     3
-atom             2    H     "OPC Water H"     1       1.008     2
+atom             2    H     "OPC Water H"     1       1.008     1
 atom             3    M     "OPC Water M"     0       0.000     1
 
 bond             1    2                  1000.0      0.8724
 bond             1    3                  1000.0      0.1594
-bond             2    2                  1000.0      1.3712
 angle            2    1    2              100.0      103.60
 angle            2    1    3              100.0       51.80
-angle            1    2    2              100.0       38.20
-torsion          0    1    2    0
 
 vdw              1                      1.77717      0.2128
 vdw              2                        0.000      0.0000
-vdw              3                        1.000      0.0000
+vdw              3                        0.000      0.0000
 
 charge           1                        0.000
 charge           2                       0.6791

example/opc.xyz

@@ -1,9 +1,9 @@
      8  OPC Water Dimer
      1  O      1.442615    0.000000    0.057481     1     2     3     4
-     2  H      0.570548    0.000000    0.032324     2     1     3
-     3  H      1.672122   -0.000000   -0.784221     2     1     2
+     2  H      0.570548    0.000000    0.032324     2     1
+     3  H      1.672122   -0.000000   -0.784221     2     1
      4  M      1.347694   -0.000000   -0.070574     3     1
      5  O     -1.358378   -0.000000   -0.045247     1     6     7     8
-     6  H     -1.789675    0.685600    0.278390     2     5     7
-     7  H     -1.789675   -0.685600    0.279390     2     5     6
+     6  H     -1.789675    0.685600    0.278390     2     5
+     7  H     -1.789675   -0.685600    0.279390     2     5
      8  M     -1.485804    0.000000    0.050517     3     5

example/opcbox.key

@@ -0,0 +1,35 @@
+parameters              NONE
+rattle                  WATER
+
+vdwtype                 LENNARD-JONES
+radiusrule              ARITHMETIC
+radiustype              R-MIN
+radiussize              RADIUS
+epsilonrule             GEOMETRIC
+electric                332.0522173
+dielectric              1.0000
+
+x-axis                  31.05
+ewald
+ewald-cutoff            9.0
+vdw-cutoff              12.0
+vdw-correction
+
+## OPC Parameters (J Phys Chem Lett, 5, 3863-3871, 2014)
+
+atom             1    O     "OPC Water O"     8      15.995     3
+atom             2    H     "OPC Water H"     1       1.008     1
+atom             3    M     "OPC Water M"     0       0.000     1
+
+bond             1    2                  1000.0      0.8724
+bond             1    3                  1000.0      0.1594
+angle            2    1    2              100.0      103.60
+angle            2    1    3              100.0       51.80
+
+vdw              1                      1.77717      0.2128
+vdw              2                        0.000      0.0000
+vdw              3                        0.000      0.0000
+
+charge           1                        0.000
+charge           2                       0.6791
+charge           3                      -1.3582