#340 Rename tactics provided by the Theory plug-in

[Laurent Voisin]

The Theory plug-in provides some tactics for expanding operator definitions and running rules defined in a theory. These tactics have hard to decipher names such as "RbP0", "RbP1", "RbPxd", etc. that should be improved (without changing the internal id which is not visible to the user).

Also "RbP" should be replaced by "Theory" in all tactic names.

[Son Hoang]

The same goes for the display names of the underlying reasoner.
Cheers,
Son