Add 'is_in_battle' db field and icon on map

[michikrug]

Description

Adds 'is_in_battle' db field for gyms and display a fighting icon on the map.

Motivation and Context

Show the users which gyms are currently under attack by adding a little icon on top of the gym image.

How Has This Been Tested?

Tested on local instance.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• 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.

[ghost]

How long does this data stay in db? I would love to collect data on gym activity.

[michikrug]

It is always just the current state when it was scanned.

[sebastienvercammen]

Tagged breaking change to refer to icon/spritesheet generation as a reminder for our devs.

[sebastienvercammen]

@michikrug Could you rebase? And thoughts on separating the "gym in battle" functionality from your other PR for image generation?

As it stands, we won't be able to merge either PR. Separating them makes merging this PR much easier.

[michikrug]

@sebastienvercammen Have rebased.

Currently, the 'is in battle' mark is completely relying on the dynamic image creating PR. Therefore, it will be hard to separate them.

I can try visualizing the battle state differently, so that it does not use the whole image stuff.

[billyjbryant]

Needs to be rebased

[michikrug]

@sebastienvercammen rebased and used a simpler way of displaying only the battle state

[darkelement1987]

So this would make things like triggering Pokealarms like 'Gym Team Valor is under attack' a possibility in the future?