Add new option to Set gems to max level when Importing From Your Account

[BenjinYap]

Adds a new option to Set gems to max level when Importing From Your Account.

Description of the problem being solved:

I use PoB like:

1. Plan a new build.
2. Start playing build.
3. After getting to around level 60-70, import build into PoB to replace Step 1.

Since I usually import before my gems reach max level, I now need to manually set all the gems back to level 20 if I want to test swapping support gems for a fair comparison.

This is a convenience feaature.

Steps taken to verify a working solution:

Tested imports with:

• Normal gems
• Convocation
• Exceptional gems

Link to a build that showcases this PR:

Before screenshot:

After screenshot:

[LocalIdentity]

This feels like an extremely niche scenario that is bound to cause issues with people forgetting that they selected it as an option

[BenjinYap]

I don't think it's much of an issue as people can just uncheck it and re-import to bring the real gem levels back, but fair enough.