Throw inconsistency error before writing files

[unfokus]

Currently in --fast mode when one router causes the inconsistency error it might happen that the files for other routers have been updated already. This also causes the error only to print for just one router, not for all affected.

Wanda should first check all routers, print all errors and then write the newly generated files.

Error: Inconsistency within filter groups for <ROUTER>, need to regenerate filter groups