Poor man's fix: add specific content type

Ideally an end user could add/edit custom content types from the banner tile configuration form.
Revert "Poor man's fix: add specific content type"

This reverts commit a229c321c5c41c7afdab94c56f69231f02bed437. Ah, OK. I was a bit confused why you wanted me to revert something on my branch but now I assume it's so we can moved forward with the "real" fix :-)
Added any content type support for banner tile
Merged CHANGES.rst
Fixed CHANGES.rst
Fix in banner tile
Merge branch 'master' into issue_241
Added test case and organized code and comments
Flake8
Merge branch 'master' into issue_241
Add Cover as Linkable in TinyMCE settings (closes #259)

@marcosfromero you owe me a beer because of the mess
Refactor test to avoid weird failure on Plone 4.2
Merge branch 'master' into issue_241
Prevent kss validation errors in Plone 4.2
Merge branch 'master' into issue_241
Merge branch 'issue_241' of https://github.com/collective/collective.cover into issue_241
Trying to fix travis builds
Trying to merge with master
Merged with master
Merge branch 'issue_241' of https://github.com/collective/collective.cover into issue_241