Avoid having multiple instances of the same app running

Especially dealing with qml projects you often have a very fast develop cycle:

• Run app
• Make a small change in .qml
• Re-run app
• Make another fix ...
• ...

Quite a few people now forget to 'stop' the app from the last run, resulting in various annoyances

• You loose track which one is the last one started
• On windows the debugging output is blocked
• For Symbian the COM port is blocked
• When debugging QML the default debug port is blocked
• At the end you have to kill lots of running apps

Easiest fix would be to have a 'Stop & Run' action with a keyboard shortcut . Or ask the user whether he really wants to have two instances of the same run configuration running in parallel / whether he wants to kill the old one.