added theta/analysis_2.py for new naming convention 

added test file to run on theta files with new naming convention

the file also includes

* reduced prior uncertainties for bkg cross sections
* toptag left unconstrained
* templates for 'wc', 'wb' and 'wlight' scale and matching systematics are supposed to be in the theta file (to properly correlated the effect of the up and down variation among the 3 processes)