Backport r829657 from trunk:

  mod_charsert_lite: Start honoring the 'NoImplicitAdd' CharsetOption.  
  Unsettable since 2.2.9, before that a no-op.

Reviewed By: covener, trawick, poirier



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@881824 13f79535-47bb-0310-9956-ffa450edef68