better error handling, adding ENDFDataSource.reaction that uses rxname to accept all rx
discretized tweaks, api improvement
Merge remote-tracking branch 'upstream/staging' into staging
This makes pictures but has Physics Problems
moving discretize back into ENDFDataSource
Merge remote-tracking branch 'upstream/staging' into staging
ENDF discretization should work, actually, for real, this time.
changing Eint to e_int because lowercase, adding slight docs
slight commenting
PEP8
docfix
Added missing 'np.' to 'e'