Fix some comments concerning LR(0) versus LALR(1).

Fix some comments concerning LR(0) versus LALR(1).

Stop equating LR(0) with nondeterminism and LALR(1) with
determinism.  That is, if all states are consistent, then LR(0)
tables are deterministic.  On the other hand, LALR(1) tables
might be nondeterministic before conflict resolution, and GLR
permits LALR(1) tables to remain nondeterministic.
* src/LR0.c, src/LR0.h: Here.
* src/lalr.c, src/lalr.h: Here.
* src/main.c (main): Here.
* src/state.c, src/state.h: Here.

* src/ielr.h (ielr): In preconditions, expect LR(0) not LALR(1)
parser tables.
(cherry picked from commit 1c4ad777cb220ea669dc934c9b600a25a824a658)