Enable -funsigned-char for linux 2.x. Put a brief comment about work in

progress into CHANGES.

PR:		800, 2252, 2553


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81666 13f79535-47bb-0310-9956-ffa450edef68