Added Jitsi license header.
Test the database connection more thoroughly

If the HSQLDB lies on a network share and the computer went into
standby, the connection still indicates that the connection is valid
while it actually is not. Check if a SELECT is posssible and recreate
the connection if not.
Update sdes4j to 1.1.3
Update libjitsi to 5c27d77ffdda40a255eef19d7588e0822c282923
Fixes a problem where we cannot start configuration service when using not writable or not accessible folder locations.
Disable MCL tests as they fail and need to be rewritten
Update libjitsi 5c27d77ffdda40a255eef19d7588e0822c282923

(Recommit, previous binary was built against Java 8)
Fix the disappearance of external contact sources
Disable XML external entities before parsing.
Updates fmj to r93.
Revert "Disable XML external entities before parsing."

This reverts commit b1e75a29614352a74693c838be234238aaa2fb0f.
Adds NPE check.
Makes possible to insert/remove global statuses other then online and offline.
Does not show statuses other than Online/Offline when there is no provider to support them.
Primitive implementation of presence watcher for Contacts.

A primitive initial implementation for periodically testing the presence
of contacts by using IRC's ISON query. Currently using a period of 60
seconds, it will check with the IRC server whether or not contacts are
online. Contact presence change events will be fired for each of the
results, both online and offline. For presence changes, the contact list
will be updated accordingly.

Additionally, presence update events will also be fired in case an
ERR_NOSUCHNICK is received. This indicates that something assumed that
the contact was online, but it turns out that this contact is actually
offline.
Improved contact presence support:

1. Support for long lists of user names by sending multiple queries.
2. Created FIFO list for nick sets. Each nick set is exactly the content
of 1 query, such that we can handle the RPL_ISON events by comparing
expected nick list with actual nick list.
3. Update presence upon receiving QUIT, channel join.
4. Escape for case when unexpected RPL_ISON is received. (i.e. list of
expected nick sets is empty)
5. Implemented subscribe, unsubscribe methods for
OperationSetPersistentPresence.
Tweaks.
Make submittedMessage volatile, just in case.
Converted sorted set to list, since we have a (already sorted) list
of nicks that we query for in a query message. (+ misc improvements)
Clean up.