filter: added simple OsmSourceAdapter

Can only handle small OSM files though, since all data is currently
still being held in memory before storing in couchDb
filter: use streaming in adapters instead of reading entire source
filter: added onComplete method to Filter

Called by FilterChainManager when data stream has been processed.
processor: filters are now seperate from source adapter

The common name for both is processor.
processor: added bulk read and write of data to DbInsertionFilter
processor: minor cleanup in CsvSourceAdapter
test: added bulk create and update test method to DataRepositoryTest
processor: added metrics gauge for running tasks
monitoring: added PauseableTimer
processor: added time monitoring to DbInsertionFilter
processor: added metricso to adapter classes

hasNext and next are measured.
test: fixed DbInsertionFilterTest
db: fixed all view in DataSourceRepository
processor: added timer metrics to Filters
processor: added IntToStringKeyFilterTest for converting int domain ids
db: DataRepository supports removing all data
test: added removeAll test to DataRepositoryTest
processor: moved sourceUrl from DataSource to SourceAdapter

That way one ODS source can contain data from multiple original sources
processor: added ability to run filter chain once

E.g. for initial batch uploading
processor: added switch fo DbInsertionFilter for direct insert

... instead of having to update first