Split p(E-value) into two metrics differing by "zero" E-value handling

OrthoMCL sets all BLAST-rounded "zero" E-values to 1e-(minEvalueExponent-1)
before inter-organism normalization. BLAST (v2.2.28+) rounds E-values less than
1e-180 to zero, which only requires a bit score of a few hundred amino acids.
BLAST hits between closely related sequences can easily generate bit scores in
the thousands, so this heuristic dramatically penalizes the most significant
BLAST hits. After normalization, some of these could be adjusted above E-values
that are more than an order of magnitude less significant.

I attempted to improve on this by setting the range of (post-inter-organism-
normalization) heuristically-restored E-values beyond that of the range of the
other post-inter-organism-normalization E-values. This normalization method
decreased the performance of the p(E-value) however, motivating me to compare it
to the OrthoMCL method.

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