Remove extra s on Contributor(s) in collections/browse
Force sorting by ID after all other sorts.

Resolves some unexpected tie-breaking situations, and bugs with tied
sorts around page breaks on MySQL 5.6+.
Update Coins submodule.
Stylize element set and item type element labels.
Merge branch 'master' into stable-2.1
Change string "Contributor(s)" to "Contributors"

Lets the existing translations use their strings. See ba547abb8558695320879d1dd6104b71fb596c08
Update translation template.
Pull from Transifex.
Bump version to 2.1.4.
Update EB and SimplePages submods.
Add configuration to filter API element text representations.
let Researchers search on non-public items and collections
Set version for 2.2-dev.
Add option for hiding element set headings.
Merge branch 'filter-api'
Add element set heading option to install.
Add extra fallback images based on mime type.

We now provide 4 fallbacks: a generic, and ones for audio, images, and
video. A function is provided for adding additional fallbacks.
Use bigger fallback icons.
Tweak video icon.
Show thumbnails for items with any files.