Proves and then stores a theorem in the current theory segment.
DESCRIBE
The call store_thm("name", t, tac) is equivalent to
save_thm("name", prove(t, tac)).
FAILURE
Whenever prove fails to prove the given term.
USES
Adding theorems to the current theory. Saving theorems for retrieval
in later sessions. Binding the result of store_thm to an ML variable
makes it easy to access the theorem in the current terminal session.