Update moodle to 1.9.9 and add postgresql variant

[ldeck]

Attaching a diff to update the moodle port to the current stable version of modle, 1.9.9.

Also adding a variant for utilising postgresql.

[ldeck]

update moodle to 1.9.9 adding postgresql variant

[jmroot (Joshua Root)]

Bare usernames don't work in the cc field, you have to use complete email addresses.

[ryandesign (Ryan Carsten Schmidt)]

Thanks for the suggestion. I updated moodle in r70599.

Instead of adding just a postgresql variant, I added postgresql and mysql variants, with mysql still being the default. This way it's clear to the user that they have a choice between PostgreSQL and MySQL, and not just a choice of PostgreSQL on or off. I also added variant descriptions. We would usually mark these variants as conflicting with one another, but in this case it didn't seem to cause any harm to let the user select both at once and then decide at runtime which they want.

Instead of adding "universal_variant no", I used "supported_archs noarch" since this port installs no architecture-specific files. This wasn't in fact 100% true: it did install some pre-compiled i386 binaries of mimetex for Mac OS X, Linux, FreeBSD and Windows. I modified the port to remove these files; if we later find we do want mimetex after all, making a separate mimetex port seems more appropriate.