It works just like regsub(), but replaces all occurrences of the regexp.

	regsub("1foofoofoo2", "foo", "bar") -> "1barfoofoo2"

	regsuball("1foofoofoo2", "foo", "bar") -> "1barbarbar2"

Fixes ticket 238



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@2640 d4fa192b-c00b-0410-8231-f00ffab90ce4