add/fix lots of gtk-doc comments

add/fix lots of gtk-doc comments

	* libsoup/*: add/fix lots of gtk-doc comments

	* libsoup/soup-misc.c (soup_str_case_hash, soup_str_case_equal):
	Fix bug noticed while documenting. (We were using the
	locale-case-insensitive functions rather than the g_ascii_ ones.)

	* libsoup/soup-message.h (SoupMessageFlags): remove the (never
	implemented) NO_PIPELINE and NO_COOKIE flags.

	* docs/reference/tmpl/*.sgml: Regenerate, fill in some stuff.
	There are still problems here with gtk-doc not recognizing many of
	the objects in libsoup...