syntax fixes and install instructions

[ghost]

[cclauss]

Bump on this one!

Related to #13

Also, Python 3 treats TabErrors as syntax errors.

flake8 testing of https://github.com/lake8 testing of https://github.com/nccgroup/redsnarf on Python 3.7.0

$ flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics

./redsnarf.py:360:31: E999 TabError: inconsistent use of tabs and spaces in indentation
		dce = DCERPC_v5(rpctransport)
                              ^
1     E999 TabError: inconsistent use of tabs and spaces in indentation
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