BUG: Revert the change to FileIsDirectory. Add FileIsSymlink and treat symlinks as files when removing directory

BUG: When removing directory, use lstat instead of stat to make sure that symlinks are treated as files and not as directories

ENH: Extended test 0 to run the executable twice using the same process object.  This tests the reusability of the objects.

BUG: Do not increment optr by 2 after storing only one character.  Also fixed possibility of storing uninitialized characters from the last triplet.

ENH: Added some smaller primes to allow small hash table sizes and therefore shorter initial construction times.

BUG: Use sleep(1) instead of usleep(1000000) because some UNIX systems specify that the argument to usleep must be less than 1000000.

ENH: fix test, it has to return a true/false value otherwise it just passes the test, and add test for EscapeChars

ENH: add convenience function to convert Windows command line args into Unix argc/argv. Pulled and cleaned from PV/VV/VJ init code

BUG: struct timeval uses unsigned types on at least one platform (QNX).  Alot of the time logic assumes a signed type.  Switch to using a signed representation that is converted to the native representation only for system calls.

ENH: Disabling test 6 on QNX until process killing can be resolved.  It will just fail always for now.