Issue #2510680 by a.dmitriiev, ikeigenwijs, smk-ka: Initial Drupal 8 port

--dev release

Entity browser 8.x-1.0-beta8
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- #2781125 by Berdir: Delete button in file browser widget not working.
- #2778923 by marcoscano, slashrsm: Propagate field cardinality to Entity browser when using it for selecitng existing entities on behalf of IEF.
- #2786851 by reekris, samuel.mortenson: Fix Removing entities in FileBrowserWidget is broken.
- #2786141 by Leksat: Correctly handle Enter key in views exposed form.

First dev version

Final version for drupal 8.2.x