Merge branch 'acsl_marshaller' of https://github.com/yoogx/polyorb-hi-c into acsl

Some files have been modify in the ACSL branch (Makefile...)
Comment Block suppressed
po_hi_message.c test files added
minor typos in Makefile.am
first specification of __po_hi_swap_bytes. Can be proved with alt-ergo
with -all-models option
add scratch directory
move __po_hi_swap_bytes specification to .h file
add po_hi_config.h in gitignore
add more tests for swap_byte
more tests for swap_byte
add goals directories to gitignore
correct implementation + specification of __po_hi_swap_byte
add RTE verification + timeout for alt-ergo
new specification and implementation for __po_hi_swap_byte using integers
correct errors in bit shifting using integer arithmetics
fix conflict in po_hi_utils.c and merge swap-byte branch
simple specification for __po_hi_get_time as we do not use the POSIX
etc. options (__po_hi_get_time always returns __PO_HI_UNAVAILABLE).

TBD: find a way to use the __PO_HI_UNAVAILABLE macro in specification.
force POSIX option and trivially change _po_hi_get_time spec (but not finished)
add invariant for __po_hi_time_t, but does not seem to be supported by
WP plugin...
add WP_VERBOSE variable to print goals and write proof obligations in
topdir/proof-obligations directory. Just use it with make wp-proof
FILES_TO_PROVE=blabla.c WP_VERBOSE=1 for instance (the integer does not
matter).