Split PD Unqiues to not depend on PD base

[adriangaro]

This PR has the purpose of splitting the PD Uniques from PD base as it could be a standalone mod.

Changes:

• Moved pd unqiues assets inside it. Common assets have been duplicated under the same name (think it only affects some color correction files)
• Moved all localization regarding pd uniques, split by unique type for easier localization in the future. Note some of the localizations has missing keys and brought them back using the english ones.
• Fixed some localization keys which seemed to have been localized in spanish (mostly the word shroud)
• Moved events and engine code related to them inside uniques. Moved is_pd_unique trigger inside the unique folder.
• Regarding triggers, moved triggers concerning submods into them. Added a bunch of them under the main pd mod to be able to easily get all pd planets, rares, gaias etc to be used for compatibility mods or even internally.
• Cleaned up reference to civics which probably dates back to before origins.