Correct typo in comment.
Add and use get_commutative_other_op().
Remove unnecessary restriction, that y in (x * y) + x must be a Const.

Also reduce code duplication.
Check the symmetric case of (x * y) + x, even if this case fails partway through.
Add local optimisation: (x * y) + (x * z) -> x * (y + z).
Cleanup.
Correct order in enum tokens.

tok_identifier is not a keyword (just any identifier).
It has not entry in reserved[].
This caused all commands after "help" to be shifted by one.
Cleanup.
Remove the unused function firm_debug_active() and flag is_active.
Use tarval_is_*(x) instead of x == get_mode_*(get_tarval_mode(x)).
Remove unnecessary special case for mode_b.

get_mode_min/max() returns false/true for mode_b.
Do not test for constants on the left hand side of commutative operations.
irn_copy_into_irg: Fix irg attributes after copying.