This is in order to better support derivative engines.
Rework the manpages to be parameterized with @PROGRAM_PREFIX@ and
@PACKAGE_NAME@. Alter the `docgen` generator to substitute those
parameters. Supply those parameters via the autofoo Makefile.
Adjust the fixed path chocolate-server.6 to be generated from
server.template, similar to doom.template -> chocolate-doom.6.
Further work is required, not least renaming chocolate-setup.6,
but several further parameterizations.
Introduce a new PROGRAM_SPREFIX variable in configure.ac, which is
basically identical to PROGRAM_PREFIX but without the trailing hyphen.
PROGRAM_PREFIX was also redefined so that it bases its name from
PACKAGE_SHORTNAME, reducing the number of hardcoded chocolates in the
source.
For out-of-tree builds we must specify the full paths to source files
using $(srcdir). Do this for all the template files and clean up some
of the confusing and inconsistent usage of source dir paths already in
place.
Only one for all four games and only static for the time being.
In the long term, we should modify the docgen script to emit the
possible valid command line parameters and their additional options
and thus create separate bash-completion scriptlets for all four
games.
