baby steps

this fixes the case where we have a SSI start tag split up
over multiple buckets.

BTW
HTTPD-test is failing.
but it was failing on 2.0.32 version of mod-include as well


PR:
Obtained from:
Submitted by:	Brian Pane
Reviewed by:	Ian Holsman


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@93555 13f79535-47bb-0310-9956-ffa450edef68