kept in mind during this are a) to reduce load time for common cases like
cgi and post-commit and b) make the code easier to navigate.
This also modularises RCS support to the extent that it should be possible
to drop in a module for some RCS other than svn, add a switch for it, and
it pretty much just work.
High chance I missed an edge case that breaks something, this is only
barely tested at this point.
checkoptions() that can be used to set defaults for this and other options
based on existing options.
Also involved some cleanups to how gen_wrapper is used.
joey