fixing broken link
Merge branch 'broken-api-docs-link'
Remove vagrant.
Don't need joindin-api submodule.
Using https to avoid the non-secure warning when going to https://joind.in

As an example: https://joind.in/event/view/2166
Updating the contributing.md file to make it clear that no further features will be accepted on web1
Merge branch 'pr809'
Merge pull request #811 from lornajane/maintenance-mode

We no longer accept new features onto this website