#1 Connection to Master can block core

[Alexander Klimetschek]

If the connection to the Master Server fails at the beginning
of the CoreService.run(), there wont be any connection
and correctly working Core until he is completely restarted.
Connection and connection data (MasterserverHost etc)
read from config.properties should be repeteatly done in
the Core's main loop.
This would make it possible to change the Masterserver
during runtime of the Core.