Dasmap hash check

1. added '###' to config, so these messages can be filtered out easily
2. dasmap validity check, fixes #4065 
  * check the validation token in DB based on all record hashes matches the calculated one
  * the validation token to be generated in:
    - das_maps tool (connecting to mongodb directly)
    - and in create_das_js (which prepare dasmaps js file for mongo)
  * load_maps will run more often if check_maps fail
    - added new config param: DASOption('mappingdb', 'reload_time_bad_maps','int', 2*60),
  * check_maps turned off in das_map tool (tools/das_mapping_db) as with short intervals it might interfare with the updates
3. to Discuss:
  * currently there are two constant reload intervals, if maps were valid and if they were not... I guess that's quite sufficient... what do you think?
  * currently we have two ways for updating DAS mappings: loading directly from yml files (das_map script) or creating json with maps (create_das_js) to be mongoimport'ed
    - is this duplication really needed? well, I understand in some environments mongoimport may not be available...