Don't crash on bad plugins.json; fixes #2323
Merge pull request #2324 from beaugunderson/no-crash-on-parse-plugins

Don't crash on bad plugins.json; fixes #2323
slight ui fix
working blocks
Merge pull request #2326 from ether/blocks-for-custom-script-and-styles

working blocks
Merge branch 'develop' of github.com:ether/etherpad-lite into new-icons