Building TWRP

Additions to boardconfig.mk in order to build TWRP properly.

CM 10 and Slimbean 3.1.0

#twrp
TW_DEFAULT_EXTERNAL_STORAGE := true 
DEVICE_RESOLUTION := 480x800
RECOVERY_GRAPHICS_USE_LINELENGTH := true
TW_FLASH_FROM_STORAGE := true 
TW_INTERNAL_STORAGE_PATH := "/sdcard"
TW_INTERNAL_STORAGE_MOUNT_POINT := "Internal"
TW_EXTERNAL_STORAGE_PATH := "/external_sd"
TW_EXTERNAL_STORAGE_MOUNT_POINT := "External"

###CM 11

TODO