replace all occurence of symbol type by itype

Emacs (with cedet-mode enabled) crashes on symbols named "type" as it
searches on a long long list of possible matches in gtags. Temporary
solution is to not use the variable name type anywhere in c++
Add OA vs photon energy histograms

- three possibilities: min, avg and asymmetry
Add python module to calculate tda cross section integrals

- Still in debugging stage. Results do not match yet publication
Run BG generation scripts with plab as argument