Keep features on config process restart.

We used to store a list of enabled features in ets table owned by `config`
process. This meant that on every `config` process restart we loose the
list. Therefore welcome endpoint start to return empty list of features.

Use application environment to keep the list.

fixes #1930
2 files changed
tree: d48a43e7c4e10b960cc67688af83fd3026190e91
  1. .travis.yml
  3. src/
  4. test/