Resolve undefined 'name' in Environments#validate

The error message for the environment name in
`Spiceweasel::Environments#validate` refers to a `name` method or
variable that does not exist in the scope of the `#validate` method.
Instead, it should refer to `env.name` to display the name within
the environment file.
Bump version for Environments#validate bugfix
Merge pull request #36 from crymer11/patch-1

Resolve undefined 'name' in Environments#validate.