Touching up README.md
Adding Plan sizes and ID as per API requirements
Merge branch 'linode_conversion' of https://github.com/displague/vagrant-linode into linode_conversion
Merge pull request #3 from scub/linode_conversion

Fixing plan_id issue to allow creation with fuzzy matching
Merge pull request #2 from scub/linode_conversion

Touching up README.md
support optional api_url
Vagrantfile/config related README.md updates