Fixed SD2-1088: Debugger throws exception clicking run command two times in a row.
Fixed SD2-1089: Debugger throws exception trying to break a project two times in a row.
Fixed SD2-1091: Debugger throws exception clicking stop debug command two times ina row.
git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@1800 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61