Submit and display more information about matches in the lobby. Patch by Imarok, refs #3476.

Includes team numbers, online/offline- and won/defeated state, AI type and difficulty for running games and
only the playernames with observer-player distinction in the gamesetup.
Use JSON format inside the XML stanza and minimize traffic by packing teams.

Use the observer distinction to correctly apply the "full games" trigger in the lobby, fixes #3143.

XPartaMupp patch applied by scythetwirler.
unescapeText function by sanderd17, refs #3409.