Don't force quoting on environment write.

Docker's environment file will escape any quotes that exist, so
make sure not to quote environment values when writing them out.
Instead, just use line separation.

If you want quoted values in your environment file, you can double
quote the values and only the first wrapper will be removed.

Fix tests.
Add an additional test case

Remerge against master and fix compile errors.  Also correct identifier
validation against EnvironmentDescriptions
Merge pull request #205 from smarterclayton/env_tests

Add additional environment support