Add Makefile to project
Add --test-speed option for testing cracking speed
Fix bug with subtraction of unsigned ints. Catch interrupt signals.
Remove unused "md5" state array
Merge branch 'speed-test'

Conflicts:
	crackxls2003.c
Only show cracking performance at exit if -t flag was specified
Add contact information to README
Count keys tested inclusive of first and last keys
Fix divide-by-zero error when CPU time = 0
Add documentaition of -t option