FIX: minor comment updated about x87 exceptions default mask.
FIX: moved x87 control word setting later in the starting sequence.
FIX: control word now correctly set for shared library generation.

The control word was overwritten by earlier system calls.
FEAT: preliminary support in compiler for literal NaN and INFs.
Merge remote-tracking branch 'origin/float' into master-oldes
FIX: Using 1.#NaN instead of 0.0 if to float! conversion is not succesful. (should be replace by error! while we will get it)