getEnvironment returns incorrect results

[drzax]

A change to the domain names used for the various preview environments available means that getEnvironment is now returning incorrect results for (non-prod) outputs.

The main change is that PL previews have been switched to use the develop deployment rather than the preview deployment. There is information about the various PL deployments available. But it all needs to be verified in the real world.

[drzax]

I propose we remove getEnvironment. I think it was initially added for completeness, but:

• I don't know of any dependencies using it
• It's not currently working
• The need for it is unclear
• The environment can't be detected by hostname as it used to be, so this would require a new detection method — effort that I don't think is necessary.

[phocks]

Agree.

[drzax]

Removed in #29