Drop support for vagrant

[taylortom]

This was discussed at the roadmap meeting.

Will involve the following:

• Removing relevant files from the repo
• Updating the wiki/removing references in the install instructions
• Potentially researching an alternative option (docker?)

[taylortom]

As agreed in the weekly meeting 8/02/17:

• Test installation on Windows 7, 8 & 10, and improve windows-specific install instructions if necessary
• Investigate Docker as an alternative

[canstudios-louisem]

We did some docker investigation which I can dig out, or is the current plan to just to drop vagrant? if so should we remove the special cases for it?

[taylortom]

I'd be most comfortable just dropping vagrant without a replacement, unless we can get several people to commit to supporting the alternative.

[canstudios-louisem]

can we close #1000 and #1006 with this?

[taylortom]

Yep!