fix(preprocessor): treat *.tgz, *.tbz2, *.txz & *.xz as binary

Tarballs often use extensions joined with used compression, e.g. *.tgz instead
of *.tar.bz.

Also, there is a new xz lossless compression format that is slower but gives
better results than gzip or bzip2.
Merge branch 'pr-1148' into presubmit-master-pr-1148
chore: release v0.12.22
docs: fixes typos and makes config filename consistent

There were some typos to be fixed in various places and there was also an
inconsistency with the name of the files used in intro/configuration.
Merge pull request #1165 from cirocosta/docs-typos-and-consistency

docs: fixes typos and makes config filename consistent
feat(init): install coffee-script automatically

if the user initialize Karma passing a .coffee file we'll install
coffee-script and put it as a dev-dependency

Closes #1152