[BUG_FIXED] Fix Project Manager's "Open Workspace" and "Reload Workspace" commands bug - without removing the old Workspace.

git-svn-id: svn://svn.tuxfamily.org/svnroot/notepadplus/repository/trunk@832 f5eea248-9336-0410-98b8-ebc06183d4e3

PowerEditor/src/WinControls/ProjectPanel/ProjectPanel.cpp

@@ -293,6 +293,7 @@ bool ProjectPanel::openWorkSpace(const TCHAR *projectFileName)
 	if (!::PathFileExists(projectFileName))
 		return false;
 
+	_treeView.removeAllItems();
 	_workSpaceFilePath = projectFileName;
 
 	NativeLangSpeaker *pNativeSpeaker = (NppParameters::getInstance())->getNativeLangSpeaker();