[LUA] Add Prester latent effect functionality

[ampitere]

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• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
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• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

Adds Prester's latent effect functionality. Prester works identically to Breeze Gorget/Belt so we simply add the proper checks for the weapon and wind element on the weaponskill then add the 0.1 fTP bonus if everything matches up.

https://www.bg-wiki.com/ffxi/Prester

Steps to test these changes

1. !addallweaponskills
2. !additem 18598
3. !immortal a mob
4. !setmod regain 3000 or !godmode
5. Use a Fragmentation or Detonation weaponskill