Simplification of hydrol.f90, see also ticket #191
Most changes regard hydrol_soil and its subroutines:
- many simplifications regarding the order of the processes
- suppression of useless parts, and abusive water conservation patches
- new diagnostics of water conservation for the main processes
- the diffusion, as solved by tridiag, creates water conservation violations, that are diagnosed and reported to drainage
- separation of hydrol_soil_smooth in two separate subroutines for over_saturation and under_residual
- the case of over_saturation is no more treated with a smoothing that keeps the excess in the soil, but the corresponding excess is discarded as runoff (either surface runoff or drainage, depending on ok_freeze and free_drain_coef)
- careful check of the diagnostic and use of mcl and mc when ok_freeze
This version works well with:
- ok_freeze + explicit_snow
- old snow without ok_freeze
Note that following problems are detected but not due to this changset:
- combining ok_freeze and the old snow leads to water conservation pbs and bands.
- combining explicit snow scheme without the soil freezing leads also to water conservation problems.
Agnes Ducharne
