Update to Fred 1444; freenet-ext v29

* Update submodules to freenet-ext v29 (legacy-27 branch, confusingly enough) and Fred build 1444. (Both current as of June 15th, 2013.)
* Update build instructions (and dependencies) to include a usable version of Bouncy Castle.
* rule changes to reflect path and build changes in contrib.

One change I'm unsure of is patching `contrib/freenet_ext/build.xml` to use the `bcprov.jar` in `/usr/share/java`.