GitLab

Main changes are:
- Real constants now offer a normalized representation usable for internal
  computations.
- Constants are no longer stored in textual form.

This also adds an mli file for apply.

As a side effect, this also modifies reflection.ml accordingly.

When many equalities have to be rewritten, using the existing rewrite transformation repeatedly wastes a lot of time in declaration and task construction.
The rewrite_list transformation rewrites all equalities first and then builds the new declarations and tasks only once.

Add an intermediary decision procedure with more expressive terms, some subtraction/multiplication examples