[api]
		-Change: op_cookie for tag_eq and tag_match; optional alloc/free function for the cookies; UPDATE PATH: add the exta void * arg in tag_match and tag_eq callbacks and ignore the value; leave the new callbacks NULL
		-Change: op cookie alloc has an enum for operator type
		-Change: custom_op is a const char *, both cookie alloc and free gets it
		-Add: implement match cookie free calls

	[doc]
		-Fix: typos
		-Fix: tutor: long example for the / should do the same as the short one
		-Change: replace contact info from direct email to indirect through html to fight spam
		-Add: document the custom operator

	[helper]
		-Add: generalize traditional integer operator parsing from gtfxind
		-Add: generalize intop comparison (macro to keep things type-independent)

	[syntax]
		-Fix: terminate match pattern
		-Fix: detect and properly indicate unterminated match pattern
		-Change: relax rules so _ is accepted in names without quotes
		-Add: grammar and API for custom operators
		-Add: save sep char as custom operator for the ~ match tag_expr

	[util]
		-Add: gtxfind - similar to find(1) but uses gentrex syntax

	[vm]
		-Fix: don't call tag_eq or tag_match on NULL node
		-Fix: [] should save NUT just like () does so that || and && within a [] does the same as if it was ([])
		-Fix: don't attempt to execute broken bytecode
		-Fix: if user API doesn't offer tag_match or tag_c_op, return false
		-Fix: printf format string compiler warning on different int sizes