Separate last-modified and etag processing into separate routines,

	and insert calls in appropriate places.  (Lotta sins covered by
	that sentence..)

Reviewed by:	Roy Fielding


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@79205 13f79535-47bb-0310-9956-ffa450edef68