Get test_app_server to run again

* We should have the buildbots compile this to make sure it still works
* I had to split two ServerApp methods to a searate C++ file to link
them in libtestappserver.so
* some fixes related to the switch to PM and better hybrid support in
jam rules; moving of MIME stuff from registrar to storage kit, merge of
Locale Kit and ICU in libbe, and a few more.
* Modified the test_app_server hwinterface and rdef file so it is not a
background app, and the window isn't floating. Otherwise, hiding the
window would leave you without a way to recover it.