Do not email invited but not accepted users.

Improve test coverage; change group.users to exclude users who have not yet accepted
their invitations.
Merge branch 'bug/dont-email-invited-users'

Conflicts:
	features/mention_user.feature
Merge branch 'master' of github.com:enspiral/loomio
Merge branch 'master' of github.com:enspiral/loomio
Merge branch 'master' of github.com:enspiral/loomio
Values page first draft
values page
WIP
Merge branch 'master' of github.com:enspiral/loomio into feature/homepage2
new homepage
cleaning up whoopsie branch
cleaning up whoopsie branch
cleaning up whoopsie branch
cleaning up whoopsie branch
cleaning up whoopsie branch
refactoring, cleaning up
Merge branch 'master' of github.com:enspiral/loomio into feature/homepage2
refactor
Merge pull request #458 from enspiral/feature/homepage2

Feature/homepage2