Make all SoloInit methods public

We have nothing to hide. =)
Use interpolation
Remove non-needed :boolean arguments from CLI options

Mixlib::CLI can guess the value from the :long/:short arguments.
Actually it looks like it is not even using it anymore.
Align CLI option arguments
Use `%w` to contruct OMNIBUS_*_PATHS arrays
Merge pull request #164 from tmatilai/cleanup

Small cleanup all over the code base