Done.

Yes, I'm happy with seeing this merged.

I replied to the comment asking about the names and I actually removed the "dump_options" from the log classes. Unless you wanted to reply to the discussion to discuss further, I'll merge this later today.

As discussed on Discord, I've done another review following Patrick's review. I focused on the high-level and design aspects and might have missed details, and I didn't do checks like trying that the output actually makes sense now, that selecting different log levels from the command line does what it should etc.

I had no high-level comments. I liked it all and think the design is now nicely improved. Apart from the review comments this looks ready to merge for me.

As discussed on Discord, this issue additionally adds support for the verbosity option for all remaining pattern collection generators (hill climbing, genetic, systematic, and manual).

I created a pull-request: https://github.com/aibasel/downward/pull/91

While working on issue964, I noticed that most of the pattern (collection) generators use a member verbosity to print who they are and some final statistics. (Some other, more complex generators, also print more output during runtime.) To avoid having a separate logger in each generator, I think each generator (base class) should have one. To prepare this change, in this issue, I want to move the verbosity member to the base classes, change the central generate method to print name and statistics and between call a new virtual "internal generate" method that each derived class has to implement instead of the previous generate method.