Initial rewrite

I pilfered the blast2graph.py program from one of my related projects. This
commit contains the initial rewrite of that program for it's current use.

Known issues:
(1) Under-use of control structures
(2) Zeros remain in E-value files
(3) Normalization method is unpredictable for intra-organism hits

Signed-off-by: Ted Gibbons <ted.codes@gmail.com>