Updating code to build with newer gcc (4.9.3) and get rid of warnings on newer libc.

Updated definition of channel_t to get rid of static variables in anonymous struct warnings.

Added the proper defines (_DEFAULT_SOURCE) to get rid of libc's deprication warnings about _BSD_SOURCE.  This required
minor code path changes replacing sigseg with sigaction.  The code was already in place, for the
old potential cygwin port.

Renamed an iteration counter to fix an issue in the nds build where there was variable shadowing.

Updated printf strings for pointers to use %p.

Fixed various pointer casting warnings.

There are still some warnings in the src/gds build process with gcc 4.9.3, those will take more work.


git-svn-id: https://redoubt.ligo-wa.caltech.edu/svn/advLigoRTS/trunk@4170 6dcd42c9-f523-4c6d-aada-af552506706e