wfs capability extension point

Added an extension point for adding wfs capability extension elements
Added wfs inspire extension which demonstrates the use of said extension point.
Work is financed by IGN
GSIP 83 - REST Extensible and customizable versions report

First commit: geoserver get versions via ReST
second release
proposed relese
adding junit tests
introducing JUnit test
change rest mapping as requested
align tests to changes
adding documentation
remove geowebcache dependency from ManifestLoader;
remove duplicated Status codes section into rest config documentation;
improve rest-config-examples-curl documentation adding version and manifest examples;
Merge pull request #85 from ccancellieri/master-REST-manifest-version

GSIP 83 - geoserver get versions via ReST
GEOS-5548 - Nested Layer Groups
German properties files modified, thanks to Stefan Engelhardt
externalized an other i18 property
externalized error message for ReprojectPage
fixed typos and changed descr. of Geometry fields
Fix WCS 1.0 cite tests failure
updated German properties (consitency)
GEOS-5574, forward porting tests (no fixes needed on trunk)
Merge pull request #106 from aaime/gsip85

GSIP 85
Merge pull request #95 from jesseeichar/wfs_capability_extension_wfs_inspire

wfs capability extension point
GSIP 91
disable SSL filter test, works locally, but not in hudson
Kicking out the dbconfig module because of GSIP 85 - Nested Layer Groups
fixed exception with generic Geometry type in WMS GetLegendGraphic
improved custom dimensions management