Merge pull request #13 from scopatz/master

have working version of actvity
removing unnecessary files
minor updates
adding decay heat to metrics script
adding initial attempt at decay heat script
working query for decay heat
added function to calculate decay heat at end of simulation
fixed sql queries to give waste transacted
fixed sql queries to give waste transacted
improved metrics to be more meaningful
adding mass flow metric
adding file to work on toxicity metric
updating main metrics script
outputting data as csv
adding input files using cyclus/cycamore as of 6/5
updating existing query scripts to reflect cyclus changes as of 6/5 - closes issue #12
updating the activity script to also give the activity at the end of the simulation
adding a better decay heat function
working on radiotoxicity script
working relative activity calculation script