Fix delete logic of single and multiple resources

Change-Id: I2387fe0fb9c257c5cf8184c10d3f290c80595cb5
Signed-off-by: Denis Knoepfle <denis.knoepfle@sap.com>
Replace some custom commands by eclipse standard commands

Now key combinations also work for some commands as Delete (DEL),
Refresh (F5) and Run Diagnosis (CTRL+F11).

Change-Id: Ieba3c99b8047ffbe35eea28041e892928cfdf02a
Signed-off-by: Denis Knoepfle <denis.knoepfle@sap.com>
Merge pull request #150 from DenisKnoepfle/master

Fix delete logic and replace some commands