switch to cumulative yields
cleared out error messages and path VnV print info from cells in several tutorial ipython notebooks.
removed error print messages from example ipython notebooks in all locations possible; made one plot inline and added to the ipython notebook so it will be visible.
made ace plot also inline.
added matplotlib inline command to examples with plots.
merged upstream into origin.
fix for setup.py
Merge pull request #575 from rachelslaybaugh/develop

cleanup of example and tutorial ipython notebooks
Merge pull request #592 from scopatz/idev

fix for IPython dependency checking in setup.py
Merge branch 'cumulative' of github.com:crbates/pyne into crbates-cumulative
Merge branch 'crbates-cumulative' into develop
fixed pep8 things
Merge branch 'develop' of https://github.com/pyne/pyne into magic
renamed tally as meshtally
tolerance and null_value now optional inputs
checks for size of tag to determine if total or not
updated comments
simplified (slightly) the if-statements