refactor non event data

Basic design:

• Shared interface:

  • abstract base-class that provides the prototypes for registration of non-event data consumers and producers: IUpdater

• LHCb implementation:

  • Service that implements the ABC: AllenUpdater
  • Service that produces specific (set of) non-event data for e.g. a sub-detector and registers it, condition registration/updates are used to call updates
  • At new run, update of all conditions is triggered by forcing a condition update with a new run number

• Allen implementation:

  • Standalone implementation of the ABC: Updater
  • instantiates and registers all required readers on construction to itself

• Registration uses identifier and a lambda that capture as needed (e.g. Constants or filename):

  • Consumer: [&constants] (const vector<char>&) -> void
  • Producer: [some_filename] () -> vector<char>

• Allow running Allen from Python to allow easy integration with LHCb stack

  • use PyROOT to load the entry point
  • suggest to use json for configuration and pass as a string from python and from main.

Currently done:

• refactor main to have function to be used as entry point for calling Allen from Python
• Python entry point using PyROOT
• branch raaij_allen_producers in Rec contains the LHCb side of things.
• Allen.py added to start Allen together with an LHCbApp that provides most of the geometry

Closes #22 (closed) , #5 (closed)