Documentation update for Vagrant version requirement

Signed-off-by: Sean OMeara <someara@opscode.com>
reformatting CHANGELOG.md for stove compat
Version bump to v2.0.1
Version bump to v2.0.2
Vagrantfile can't find vagrant-omnibus correctly

The string for detecting the Omnibus plugin has changed: `Omnibus` ->
`vagrant-omnibus`.

Obvious fix.
Merge pull request #38 from docwhat/patch-1

Vagrantfile can't find vagrant-omnibus correctly