Resolve "Python 3"

Closes #3

See merge request passoft/refscrub!2

Caused by a difference between structure unpacking and the handling
of byte literals.

Also, need to open the file in binary mode or else we will have
unicode issues with reading.

Updated for Python 2.7 & 3.6 compatibility.

Code cleanup for PEP 8 standards.

add conda recipe, update entrypoint

See merge request passoft/refscrub!1