BISMG:SarahS/jules merge

Notes on merging AW glacier code to current JULES trunk
 * Install tkdiff


 * Create 3 directories in the puma repository in my work space to contain
 * 1. A copy of the trunk to which changes will be merged to
 * 2. Andy Wiltshire's code
 * 3. JULES version 3 from which Andy made his changes

Queries on merging
 * snowpack.F90 - Do I need the #if_defined statement at the top of the file?


 * In AW's version (r1044) of JULES create a new subroutine to calculate smb called tile_smb. Put subroutine into ICE directory remember to modify Makefile in ICE directory to include the new subroutine
 * call tile_smb from control.F90
 * save smb variable to offline_diag. Note this is only used for offline JULES. Put here temporarily as it is following what Andy did but may need to change this in the future
 * What is the difference between
 * ei_ice_tile(land_pts,nice) Sublimation on ice tiles (kg m-2 s-1) and
 * ei_tile(land_pts,ntiles)  Sublimation of snow (kg/m2/s) where ntiles = 59 ? Which should be used to calculate smb?
 * I have put smb in the offline_diag list but should this be in a better place? Watch out that variables in offline_diag are not deallocated!