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
It (the name) will probably not change but why should an assumption be made at all. My logic is that anything that is supposed to be "the same" in several places should be a const/variable thus avoiding potential problems in future when someone does make a change (to a name, say next developers invent weights too and move "e5x5" to "e5x5noWeight"; or whatever I don't want to foretell the future).