* convert documentation to reStructuredText
* switch from mkdocs to sphinx
* rewrite README.md (now .rst) to include less information and be more
attractive
This defines Linux, FreeBSD and OpenBSD VMs and creates a Go
environment.
Micro-tutorial:
$ vagrant up freebsd
[wait...]
$ vagrant ssh freebsd -c 'cd restic/restic; go test -v ./...'
[test output]