man: build static man pages using xorg patterns

man: build static man pages using xorg patterns

The section number is no longer hard-coded, supplied by xorg-macros.
The left footer is now "X Version 11".
The center footer is the package name with the version, "libxcb 1.9"
The man directory is a sibbling to the doc directory. One can build
or clean the man pages without disturbing the library code.

Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Gaetan Nadon <memsize@videotron.ca>