Fix typos in documentation
Adds failing test for issue #351
Fixes issue #351, where the reordering of list-items was not reflected in the DOM.
Update changelog and contributors
Try to work around travis having problems with Drag & Drop
Add documentation for the new grid system option.
Merge pull request #356 from collective/issue_351

Fixes Drag&drop list sorting not being updated correctly on the first try
Add warning message about deprecated Image and Link tiles (refs. #218)
Define logger only once in upgrades.

The steps are only called with a logger argument when you call them from your own code,
for example an import step that passes the portal and the logger to these functions.
But that does not happen in our code.
Add test for upgrade from 6 to 7.
Make upgrade step title nicer.

No underscores needed here.
Use own permission for layoutedit tab.

Permission is: 'collective.cover: Can Edit Layout'
Upgrade: only set layoutedit permission.

This is nicer in case someone has changed the cover type in his site.
Fix layoutedit tests.
Merge pull request #359 from collective/maurits-layoutedit-permission

Use own permission for layoutedit tab
Add La Jornada to the list of sites using collective.cover
Show the tile type on the compose tab:

This shows the type of a tile (Basic Tile, Collection Tile, etc...) in the
top right of the tile on the compose tab.  This makes it easier for the user
to know how they can add content -- especially if the user does not have
enough permission to view the layout tab.
Adds failing tests for #348
Hides 'please add..' text in all views but the compose view. Fixes #348
Updates changelog.