Cleanup of unnecessary and redundant files

-Removed src-i386, src-x64
-Removed .R~ and .cpp~ files, temporary files from text editors?
-Removed CR-gengeno.R, src/sim.c, src/rngs.c. These are all replaced by
generateGenotypes.cpp
-Minor changes to cpp code to remove a couple of signed/unsigned warnings.
Code now compiles without warnings.
Updated .gitignore for src-i386 and src-x64