Changeset 2291 for trunk/ORCHIDEE

Minimize acces to disk during simulation. 2 new variables in run.def :

• OK_HISTSYNC=y/n : Syncronize and write at each time step the IOIPSL output files. OK_HISTSYNC=n by default.

• NBUFF : Number of time steps of data to buffer between each reading of the forcing file. Default NBUFF=1: only read one time step at a time (as before). NBUFF=0 : read full forcing file(recomanded for site simulation). NBUFF>1 read several time steps together. This is done by a wrap of flinget: flinget_buffer is a new subroutine that calls flinget in IOIPSL and buffer the data if NBUFF/=1.