Juan 12/12/2016: configure, for ECMWF , switch by default to new ifort compiler, old cray cdt/1.15_8.2.7 in 2nd choose

(cherry picked from commit a7a6578a)

Philippe 09/12/2016: re-added #ifndef MNH_SP4 to prevent problems when compiling on Blue Gene/Q with -qautodbl=4

(cherry picked from commit 9746cd3e)

(cherry picked from commit 7a1e8bc2)

Revert "Christine 25/11/2016 : Correction on the flag for Strang splitting to insure reproducibility between START and RESTA"

This reverts commit d4b7d37a.

Christine 25/11/2016 : Correction on the flag for Strang splitting to insure reproducibility between START and RESTA

(cherry picked from commit 532f44d0)

(cherry picked from commit c3ec51f7)

(cherry picked from commit e387e7c8)

(cherry picked from commit 94c4a2a8)

(cherry picked from commit b6151050)