syntax for mod_b*.xml and mod_c*.xml

Cleanup effort in prep for GA push: Trim trailing whitespace... no func change

Update documentation for AddOutputFilterByType move

Clarify the documentation for mod_buffer to better explain where the buffer might be useful, and that buffering is not guaranteed to improve performance in all cases.

* Fix properties. Submitted by: Takashi Sato <takashi lans-tv.com>

mod_buffer: Optional support for buffering of the input and output filter stacks. Can collapse many small buckets into fewer larger buckets, and prevents excessively small chunks being sent over the wire.