Merge pull request #84 from jjacob/master

Some final updates to ensure all scripts work and all files are named correctly after recent changes.
Moved all the cross section config pieces into config.XSectionConfig
added experimental config that would allow for smarter things
added space between command and "&"
Cleaning up data/* and moving old unfolding.py to legacy
Some cleaning up
Added an exception for trying to unfold zero data, added unfolding unit tests
Fixing some warnings
Merge pull request #86 from senkin/unfolding-tests

Unfolding tests
Merge pull request #85 from kreczko/config_changes

Config changes
Added the tag instructions
Added the ratio plots, updated k-values, fixed some cosmetics
Merge pull request #90 from senkin/ratio_plots_etc

Added the ratio plots, updated k-values, fixed some cosmetics
updating external modules
enabling ROOT 6 build
fixed issue #89
removing RooUnfoldTUnfold as it is no longer built in RooUnfold (problems with ROOT 6)
refactored the old ntuple info script (legacy) into the current framework
adding RooFit examples
updated TopAnalysis make file for ROOT 6