Weather entity state based icon

[golles]

I wanted to raise a feature request for this, but realized I could easily write the code for it.
I've used this as the source: https://github.com/spacegaier/frontend/blob/dev/src/data/weather.ts#L71-L86

Description

Weather entity will have an icon matching with its state, like the standard HA entity cards.

Related Issue

I didn't want to bother you with an issue with something I could implement myself.

Motivation and Context

Making the cards better

How Has This Been Tested

I haven't tested this

Types of changes

• 🐛 Bug fix (non-breaking change which fixes an issue)
• 🚀 New feature (non-breaking change which adds functionality)
• 🌎 Translation (addition or update a translation)
• ⚠️ 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.
• I have tested the change locally.

[golles]

I wanted to order cases alphabetically but noticed these are in no particular order.

[piitaya]

Hi 🙂
Thanks for the contribution! 🙂
I'm working on another PR to clean all code imported from HA and custom card helpers so I will certainly refactor this part of code but we can merge it!