Add "New Spawn" group to fix issue #2469.

[BrownSlaughter]

There is a current issue of a brand new pokemon spawn and it will not be set a rarity until the dynamic rarity filer is updated.

We could set all new pokemon to ultra rare but for people who dont update rarity often this would mean things as common as pidgey would stay ultra rare until rarity file is next updated.

This way sets all new pokemon as a "New Spawn" and once the rarity file is updated it will be sorted properly. I added "New Spawn" to notify by rarity on the side bar and also included it in scale by rarity.

This will fix Issue #2469

How Has This Been Tested?

Tested on a live map and simulated new spawns to test it

Types of changes

• [ x] Bug fix (non-breaking change which fixes an issue)
• [x ] New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[sebastienvercammen]

• Missing update to get_pokemon_rarity in utils.py to return New Spawn for new spawns.
• updatePokemonRarities is only called once in the JS, so new spawns will stay new spawns until the visitor refreshes the page after a Pokémon has been scanned.
• 0 entries in DB = no data in rarities file = "New Spawn". But 1 entry isn't enough to define its rarity. (Arguably a problem that fixes itself with dynamic rarity and calling updatePokemonRarities on a timer.)

[darkelement1987]

Is webhook support possible for 'New spawns' ?

[darkelement1987]

Did you consider adding the 'New spawns' to the rarity exclusion filter? Also does this work with 'Hide Unnotified'?