re PR c++/28288 (ICE with min/max operator)

	PR c++/28288
	PR c++/14556
	* operators.def: Remove <?, ?>, <?=, and >?= operators.
	* parser.c: Remove CPP_MIN, CPP_MAX, CPP_MIN_EQ, and CPP_MAX_EQ.
	(cp_parser_warn_min_max): Remove.
	* include/cpplib.h: Remove <?, >?, <?=, and >?= tokens.
	(CPP_LAST_EQ): Change.
	(CPP_LAST_PUNCTUATOR): Change.
	* expr.c (cpp_operator): Remove MIN and MAX.
	(reduce): Remove CPP_MIN and CPP_MAX.
	(num_binary_op): Ditto.
	* lex.c (_cpp_lex_direct): Ditto.
	(cpp_avoid_paste): Remove ? as legal symbol after > or <.

From-SVN: r116140