Flake8 cleanups.
First version of a parser for RNAalifold ps files

This will parse the postscript files generated by RNAalifold to produce both the
2D pairing information as well as the information to draw the 2D structure as a
pretty airport diagram.
Rename and complete first version.

I've renamed this since the ps file produced is actually from RNAplot so this
has been renamed to reflect that. In addition, I've added a first simple
version of the parser. It can load pairs, locations and sequence from a simple
file. The locations likely need to be converted from lower left to upper left
to be usable outside postscript, but I'll need to check.
Add a sanity check for loading pairs.
Extract bounding box from postscript.

This may prove useful when using the plotting data in svg.
Merge branch 'develop' of github.com:BGSU-RNA/RNA-Structure-utils into develop