web staff : dynamic apache index delivery

web staff : dynamic apache index delivery

Generic apache config wasn't working, since different apps create
arbitrarily nested URL parameters, which means each app would need its
own Apache rewrite configuration to sort them all out.

This creates a new OILSWebStopAtIndex EGWeb.pm option which tells the
code to check for the presence of an index file at the current directory
as it's looking up the directory tree for the requested template.

Example w/ stop-at-index enabled.

The code will look for these templates in this order:

URL -> /eg/staff/circ/patron/142/holds

1. staff/circ/patron/142/holds.tt2
2. staff/circ/patron/142/index.tt2
3. staff/circ/patron/142.tt2
4. staff/circ/patron/index.tt2 -- file exists, all done.

Signed-off-by: Bill Erickson <berick@esilibrary.com>