Add iNat taxa lookup command

[synrg]

A taxa lookup would be a nice 1st feature for #12 , with initial support for a unique match (w. thumbnail). Later, add paged output of matching results when not uniquely matched.

See http://api.inaturalist.org/v1/docs/#!/Taxa/get_taxa and the by-id variant above it.

It was pointed out in #birds @ iNat Discord that the 4 letter shortcodes for birds are in iNat, so this is a twofer. Rather than coding something separately for that (e.g. see input_parsing in https://github.com/dfloer/discord-birdbot ), we could take advantage of that.

I envision:

[p]inat taxon bbpl

Since this uniquely matches https://inaturalist.ca/taxa/4892-Pluvialis-squatarola it would then respond with an embed that:

• Includes the rank, name, & preferred common name.
• Includes a link to the page on inaturalist.org.
• Includes description, up to some reasonable maximum length (i.e. Source: Wikipedia, usually).
• Includes a thumbnail of the cover image.
• Includes some stats (e.g. total # of observations, etc.)

Similarly, when the binomial name or taxon_id is given, it should show just the one record, e.g.

[p]inat taxon pluvialis squatarola
[p]inat taxon 4892

Example API call & output:

$ curl -sl https://api.inaturalist.org/v1/taxa?q=bbpl | python -m json.tool
{
    "total_results": 1,
    "page": 1,
    "per_page": 30,
    "results": [
        {
            "observations_count": 5304,
            "taxon_schemes_count": 10,
            "ancestry": "48460/1/2/355675/3/67561/4783/4888",
            "is_active": true,
            "flag_counts": {
                "unresolved": 0,
                "resolved": 1
            },
            "wikipedia_url": "http://en.wikipedia.org/wiki/Grey_plover",
            "current_synonymous_taxon_ids": null,
            "iconic_taxon_id": 3,
            "rank_level": 10,
            "taxon_changes_count": 0,
            "atlas_id": null,
            "complete_species_count": null,
            "parent_id": 4888,
            "complete_rank": "subspecies",
            "name": "Pluvialis squatarola",
            "rank": "species",
            "extinct": false,
            "id": 4892,
            "default_photo": {
                "square_url": "https://static.inaturalist.org/photos/10603462/square.jpg?1505927973",
                "attribution": "(c) TroyEcol, all rights reserved, uploaded by Declan Troy",
                "flags": [],
                "medium_url": "https://static.inaturalist.org/photos/10603462/medium.jpg?1505927973",
                "id": 10603462,
                "license_code": null,
                "original_dimensions": {
                    "width": 1024,
                    "height": 683
                },
                "url": "https://static.inaturalist.org/photos/10603462/square.jpg?1505927973"
            },
            "ancestor_ids": [
                48460,
                1,
                2,
                355675,
                3,
                67561,
                4783,
                4888,
                4892
            ],
            "matched_term": "BBPL",
            "iconic_taxon_name": "Aves",
            "preferred_common_name": "Black-bellied Plover"
        }
    ]
}

Support for user-specific regional & personal stats would be a nice future enhancement, giving something that the web doesn't directly support (i.e. user needs to navigate to "Show yours" to see those). That would require that the user authorize the bot with an API token of their own.

[synrg]

• If the lookup failed to return any responses, display an error message.
• If the lookup returned more than one response:
  • Check the responses to see if there is one and only one of the responses that either exactly matches the name or exactly matches the preferred common name. If there is, it is considered unique.
  • If the term was 4 letters long & one and only one of the matches is a bird, consider that a unique match and display it.
• If there is no unique response, say so, and display a link to "View results on inaturalist.org" so that there is at least that (until paged responses is added in a future version).

[synrg]

See https://api.inaturalist.org/v1/taxa/4892 for full output of all taxa info for the example unique match, from which much of the info specified above can be obtained.

For example, summary of wikipedia description up to a reasonable max length is results[0]["wikipedia_summary"]:

The <b>grey plover</b> (<i>Pluvialis squatarola</i>), known as the <b>black-bellied plover</b>
in North America, is a medium-sized plover breeding in Arctic regions. It is a long-distance migrant,
with a nearly worldwide coastal distribution when not breeding. The genus name is Latin and means
relating to rain, from <i>pluvia</i>, \"rain\". It was believed that golden plovers flocked when rain
was imminent. The species name <i>squatarola</i> is a Latinised version of <i>Sgatarola</i>, a
Venetian name for some kind of...

Also, there is a list of photos at various sizes, e.g. there is results[0]["taxon_photos"]["url"] which is:

• https://static.inaturalist.org/photos/10603462/square.jpg?1505927973
  • suitable for a thumbnail
  • remember to include attribution for the image