Symbian: Let SymbianDeviceManager handle TrkDevice leases.

...making use of a shared device by all clients. Detect device removal by
delaying the WM_DEVICE event handling. Introduce Acquire/Release mechanism
to SymbianDeviceManager and let acquire() fail if the device is in use, thus
preventing starting 'run' while debugging is active, etc.
Handle "Device removed" (unplugging of cable) signal by closing the device and adding
handlers to the clients, stabilize TrkDevice against it.
Remove communication type from the run configuration parameters (now handled by
SymbianDeviceManager).

Working towards keeping the Trk-connection always open and a giving the target pane
a meaningful tooltip.
For the moment, pass on tooltips from device manager additional information
(Trk version and such as determined by the launcher).

src/plugins/debugger/debuggermanager.cpp

@@ -224,7 +224,6 @@ const char *DebuggerManager::stateName(int s)
 DebuggerStartParameters::DebuggerStartParameters()
   : attachPID(-1),
     useTerminal(false),
-    remoteChannelType(-1),
     toolChainType(ProjectExplorer::ToolChain::UNKNOWN),
     startMode(NoStartMode)
 {}