This commit handles 2 things:
1) the merging of the `py_utils.context()` into the evaluation context
returned by `BasicModel._getEvalContext` to access the same time-related
keys,
2) the addition of 2 new keys into the `py_utils.context` (thus
transmitted to the basic model): `today` (an alias for the already
present `current_date`) and `now` which represents the current date and
time value.
Task 2269697
Julien Mougenot
669c2ebaec