Closes #49. Removed edit buttons, added geo combobox

Removed the buttons to modify the map in GeometryChooserPanel, thus the
user can not add a polygon to that map.
The user now has to draw a geometry in the cismap and can then choose
the right geometry via the DefaultCismapGeometryComboBoxEditor-combobox.
 #49 made GeometryChooserPanel disposable
Merge branch 'feature/49-improvements-geographic-properties-panel' into dev