Common Isolation & Selection Frameworks 72X Edition

#4685 + Code review comments and improvement of user interface.
Update of TWiki to come soon.

Also integrates code into MiniAOD, right now only electron IDs are embedded.

No ID code is run in the standard reconstruction at present.
We will need to talk to Validation/DQM about how to port the IDs that are used there into the framework.

Backports: 71X - #5015, 70X - #5014

@ikrav @Sam-Harper @arizzi
You notice I am sensitive to repetitions (probably because I spent too much time  debugging my own typos/misprints). I suggested to Slava some more general treatment about "constants" in CMS and this may see light some day. Anyway, although there are no real constants in python wouldn't it be better to put together few of the common ones (ebCutOff, ebMax, ebMin,...), probably named *_Const or something, and import them when needed instead of redefining them in every file? Maybe more generally these can also be read by a C++ class (so not to repeat that in the C++ code). To give the bad example I know - I did see in past 1.4442 and 1.442 used for one and the same purpose. I am sure you did all right here but you get my point. What do you think?