The problems was that visual editor is the default editor at
en.wikipedia.beta.wmflabs.org, and the test was expecting source editor.
The test now works also locally, using mediawiki-vagrant.
Removed headers from some files. We no longer use those headers.
Removed cucumber tags we no longer use, mostly internet explorer.
Added missing dependency (rake) to gemfile.
Bug: T126463
Change-Id: Ia5809f40719a2fe0c6c94338072a38765fa5c87b
