Add Python 3.x + multi-CPU support to rurasort

[rarecoil]

rurasort came up on the hashcat forums again recently in this post by Royce. i noticed it was out of date (requiring Python 2.x) and another poster decided it was really slow for him, as he was trying to process rather large wordlists. this pr makes some modifications to rurasort:

• uses 2to3 to allow for python 3 support
• fixes inconsistent tab/space indentation
• adds multiprocessing support for multiple cores (increases CPU and memory usage, and is generally slower for smaller wordlists)
• adds a pip requirements.txt with dependencies
• adds .gitignore so I didn't check in my virtualenv

i have limited dirty data to test this on right now, so please test a fair amount before merge if you decide to accept the pr.

[bitcrackcyber]

Hi rarecoil,
thanks for the updates. Its been a while since we've worked on rurasort but will be looking to implement changes - in particular and most importantly getting it to Python 3 first.

[rarecoil]

Good to know that this will help, then. This PR will work under Python 3.