Fix rl config

[fabioseel]

Finally got the RL config working again

added a working config to the examples
made necessary changes to the rl framework + related modules to adapt to config changes

most notably I needed a function building the Brain from a DictConfig for better interfacing (and in order to not duplicate code)

[alex404]

Seems fine, I guess it was mostly linting outside of cleaning up the configs?

[alex404]

Not sure if you use this it all, but you can probably delete this module.

[fabioseel]

yah mostly. There were some things I wanted to look into / compare, but maybe I can add @ deprecated for now already
(rest of this will be addressed in #35 )

[fabioseel]

Seems fine, I guess it was mostly linting outside of cleaning up the configs?

More or less. Actually since you changed the constructor of Brain I had to make several changes down the line, basically whereever I'm interfacing to sample factory to use the brain...
most importantly those changes can be seen in main > I factored out the block that sets up the brain into a function

also you had a check whether the config contains an optimizer which I removed. Are there cases where a config can be created without an optimizer? In any case, the config processing should be separated from the main function imho (opened a ticket for that #52)