Revamp autogen.sh to call functions from a Perl module

Revamp autogen.sh to call functions from a Perl module

This cut moves all of the logic from the individual scripts that
autogen.sh used to call into a self-contained Perl module. We use
OpenILS::Utils::Cronscript to avoid much of the init dupe code.

Note that calling Perl functions from a bash script is not crazy pretty,
but perhaps in the long run autogen.sh becomes something else. This is
just a step towards consolidating those functions in a single module
while maintaining the same interface as before.

Signed-off-by: Dan Scott <dscott@laurentian.ca>