Fixed some wrong displayed error messages in the UI.
Did some minor cosmetic changes in SpotterServiceClient concerning
exception messages and removed not needed methods.

Changed responses of SpotterService to always contain some meaningful
error messages even when it's just the name of the exception thrown when
no more information was provided.

Change-Id: I582faf47e9e69be839caec70b40a7eafbfd3cd9e
Signed-off-by: DenisKnoepfle <denisknoepfle@gmx.de>
Implemented usage of default hierarchy file located in the root
directory of the execution path of the UI (e.g. the eclipse folder).
Later the default hierarchy will be fetched from the server instead.

Change-Id: I1147814191c599a820e47e917ca0dbe5cc1ad2cc
Signed-off-by: Denis Knoepfle <denis.knoepfle@sap.com>
Changed extensions add dialog to be similar to the add properties
dialog.

Added scrollbars to the description text in the add dialogs.

Fixed a bug when caching the extension descriptions in
ServiceClientWrapper.

Added scrollbars to the resources list.

Change-Id: I7d2d579a7c8963cbc9786b1bcac67129f40d3305
Signed-off-by: Denis Knoepfle <denis.knoepfle@sap.com>
Merge pull request #32 from DenisKnoepfle/master

Default Hierarchy Configuration and new Extensions Add Dialog and other improvements