CMake: now ENABLE_DEBUG and ENABLE_LOGGING are options
models: now models exchange global id

Now, each model exchange Id in output and external transition functions.
The template Value is now an integer.
main: Adding main parameters to change begin and duration

- main accepts '-s begin,duration' parameter (e.g. -s 0,5) to assign the
  begin of the simulation and the duration.

- The duration parameter is shared in vle::Context parameter.
main: assigning a maximum of verbosity
models: showing events in NormalPixel external transition