fixed all the warnings given by the Portland and Cray compilers on a Cray at ORNL.
In particular, renamed all the variables or functions that had the same name as Fortran intrinsics
(although that is correct in Fortran, it can be confusing and it also confuses syntax highlighting,
and the Portland compiler prints a warning for each of them)
Merge pull request #121 from komatits/devel

fixed all the warnings given by the Portland and Cray compilers on a Cra...