grapher: use wave module instead of scipy.io
callset: add CallSet.entry access method
Merge branch 'master' of github.com:tgoodlet/NLA

* 'master' of github.com:tgoodlet/NLA:
  benchmark.py: add options argument to toggle between csv vs. .txt output
  change .joins to os.path.joins so that you don't have to run the nca_env scripts from within the callset, tried to use  the clear-annotation tool but that failed miserably