Support Hierarchical and Array of Keys

[nibinqtl]

The main changes:

1. Allow the key to be an array in the location data. For example:

[ 
  {
    "key": "US",
    "latitude": 37.09024,
    "longitude": -95.712891,
    "name": "United States"
  },
  {
    "key": [
      "US.CA",
      "US-CA",
      "US_California"
    ],
    "latitude": 36.17,
    "longitude": -119.7462,
    "name": "California"
  },
  {
    "key": [
      "US.IA",
      "US-IA",
      "US_Iowa"
    ],
    "latitude": 42.0046,
    "longitude": -93.214,
    "name": "Iowa"
  },
  {
    "key": "Unknown",
    "latitude": 66,
    "longitude": 66,
    "name": "Unknown"
  }
]

2. Support hierarchical keys with segments delimited by '.-_'. The longest match at a segment boundary wins. For example, with the location data above, a key of "US.CA.PaloAlto" will be matching "US.CA". "US-Unknown" will match "US".
3. If the location data has an entry with key="unknown", this entry will be returned for any un-matched input data.
4. Added a built-in location data file "world_regions", with 2 letter country code and provinces in China and states in the US.
5. Made circle area (instead of radius) to be linear in data value.
6. Added 'kMGTP' unit to the data value

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✅ nibinqtl
❌ grafana user

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[amotl]

Hi @nibinqtl,

we kind of took over development with our canonical fork [1], you can find setup instructions at [2]. We are semi-actively maintaining this codebase and would appreciate your contribution there very much!

Eventually, we will integrate all of those accumulated improvements we are maintaining there back into mainline.

With kind regards,
Andreas.

[1] https://github.com/panodata/grafana-map-panel
[2] https://community.panodata.org/t/grafana-map-panel/121#setup