Code formatting: indentations
SpaceControlClient: track the connection status.

Implements the gloox::ConnectionListener and tracks the connection status, which can be retrieved to decide wheather a connection should be re-established.
Fix in I3C Client: Also delete the SpaceControlClient
I3C Client: add CXX11 featureset in CMakeLists
I3C Client: reconnect on connection errors
I3C Client: Wait a second before reconnect
I3C Client: add disconnect reason to error message
Merge pull request #31 from penguineer/xmpp-reconnect

I3C Client: XMPP reconnect
[REVIEW] Daemon: Storing PIDs is always successful when no path given.

This follows the logic of having no PID file when there is no PID path, i.e.
the PID is virtually stored in the sense that storing did not fail.