Merge branch 'develop' into merge/20190517

.gitignore

.gitlab-ci.yml

CHANGELOG.md

COPYING

README.md

config/config.exs

config/test.exs

docs/api/admin_api.md

docs/api/differences_in_mastoapi_responses.md

docs/api/pleroma_api.md

docs/config.md

docs/installation/debian_based_en.md

docs/installation/debian_based_jp.md

docs/introduction.md

lib/mix/tasks/pleroma/conversations.ex

lib/mix/tasks/pleroma/database.ex

lib/mix/tasks/pleroma/emoji.ex

lib/mix/tasks/pleroma/user.ex

lib/pleroma/activity.ex

lib/pleroma/bbs/handler.ex