v2.1.0 improvements

[Austin Jackson]

1. Further improve library usage, something like this...

>>> import scanless
>>> sl = scanless.Scanless()
>>> sl.scan('scanme.nmap.org', scanner='hackertarget')
{'pretty_output': '...', 'raw_output': [(22, 'open'), (23, 'closed'), ...]}

2. Output colors on CLI using crayons.
3. Move random.choice funcs into a util.py or something
4. 3.6 in setup.py, whoops.

[Austin Jackson]

Done :)

Most of the core work in these commits:

• cceaee3
• 70876ab