partway through chainsolve decay refactor when a bug in fundemendal data was found.
ensdf reader update to grab approximate rates
reverted change.  This needs more thought.
more tansmute meanderings
Couldn't figure out @gonuke's des=0.0 trick in 2 hrs.  This'll have to wait for v0.4
adds some lines to the installation instructions in order to keep folks from seeing issue #177
made the instructions slightly more clear.
needed quotes
review responses`
Merge pull request #179 from katyhuff/mac_env

Mac env installation instructions
Merge pull request #175 from scopatz/decay-fix

Decay fix