#63 added the geometry function radio buttons

Added the two radio buttons and en/disable them when it is needed. Also
add the right geometry function to the server search.
 #63 restricted the enabling of the radio buttons

The radio buttons should only be enabled when the whole panel gets
enabled and the geometry is selected.
 #63 avoid NPE in showDescriptionOfSelectedTag()

When the description of a tag was null, then a NPE was thrown.
#66 Mockups of Search Dialog updated
 #63 i18n the class ResourceWindowSearch
 #63 the radiobuttons were not in the same group
Merge branch 'feature/63-add-radiobuttons-to-resource-search' into dev