filter: added OdsAdapter and OdsIteratorAdapter
filter: added DataSource reference to filter steps
data: visitor pattern for DataSource
translator: added PegelPortalMvTranslator
translator: made translators singelton
grabber: added GrabberFilter and GrabberVisitor
filter: made OdsIteratorAdapter final, not abstract
grabber: removed obsolete grabbers
db: moved db insertion to DbInsertionFilter
filter: OdsIteratorAdapter needs two generic params to function
data: ListObject implements Iterable
main: added IteratorAdapter to filter chain middle
db: CouchDbAccessor no longer inserts schema on data insert
db: moved all on time initializations from filter to DataGrabberMain
main: further initialization and data update in DataGrabberMain
filter: remove IterFilter

Switching between source and item iteration style results in various
ugly hacks, besides eliminating all knowledge about a complete data set.
main: removed delete db on updateData in DataGrabberMain
notifications: added SimpleNotificationFilter
main: clear and reload all sources in DataGrabberMain

... as couchdb doenst allow insertion of same object twice, even if db
was deleted in the meanwhile.
integrationTest: fixed compiler problems