Location API: use consistent naming for the API.

- Change all instances of "GEOLocation API" to "Location API"
- Treat "location-aware" as a compound word.
- Fix a typo for "general"

I used my best judgment to conclude that "Location API" is
preferred over "GEOLocation API".. if nothing else it makes
more sense because "GEO" isn't any kind of acronym or initialism.
location_api: reorganize for better flow.

- Explain why they might need it.
- Describe how they come to have it.
- Tell them what's available.
- Show them how to use it.
- Note development differences.

The "Is it snowing?" example code no longer aligns with the live
code, so just repurpose it as the example of what they will get
in the `duckpan` environment.

Reorganize and tidy up the example data to make it match the order of
attributes in the displayed code and align for easier scanning.

Add a link to how to use in testing.
Merge pull request #41 from mwmiller/location

Location API changes.