Dropped filing Checker and Excel report.

They have benn already moved to `opengever.maintenance`.
Removed not used and senseless filing_number getter in document byline.
Moved filing number setup into a separate profile.
Added IFilingNumberActivatedLayer browserlayer

To mark installations with filing number support.
Advancedsearch: display filing field only in filingnbumber suppoted sites.
Moved filing_no field in to a separate behavior.
Adjust resolve process: only show archive form, for sites with filing number support.
Dosier reporter: implement filing columns conditionally

The columns with filing number content, should only be displayed in sites with filing number support.
Reworked filingNumber indexer: are only active when filing number behavior is active.
Adjust archiver: the filing number field was moved in to a separate behavior.
Dossier tabs: Moved filing no column in to a FilingNumber specific dossier view addition.
Added upgradestep wich migrates the filingnumber from the old in to the new field.
Dossier byline: only display filing number in sites with filing nummber support.
Merge pull request #137 from 4teamwork/pg_filing_nubmer_exclusion

Filing number exclusion