Factor common code into a common place
clean old comments
Checking for POLYGON bounding-box is OGD version-specific
correct specification for OGDAT V2.2

the machine translation was not that successfull
fix test
kind of resolve a TODO
add minimal metadata

define a very small metadata scheme
extract schema version out of that minimal common metadata
use the common subset to log into database
add new metadata fields of OGDAT V2.2 to check routine
respect new OGDAT version 2.2 in watcher
test file for MinimalMetaData and version extraction
add missing language file for OGDAT V2.2 checker