fix(feats): Add features from several sourcebooks

[justinyates887]

What does this do?

\This push aims to add several feats to the API

How was it tested?

<It's not clear if I don't update this text with relevant info>

Is there a Github issue this is resolving?

\No issue currently

Did you update the docs in the API? Please link an associated PR if applicable.

<It's not clear if I don't update this text with relevant info>

Here's a fun image for your troubles

Notes

• Feat Aberrant Dragonmark has a unique prereq, check key.
• Feats Eldritch Adept, Elemental Adept, Metamagic Adept, Spell Sniper, War Caster contain prereqs for features Spellcater and/or Pact Magic, which are not present in Features
• Feats Fighting Initiate, Heavily Armored, Heavy Armor Master, Medium Armor Master, Moderately Armored require proficiencies, which I was unable to find refs for. Needs review.
• Feats Drow High Magic, Wood Elf Magic point to subraces that have not been populated.
• Missing sourcebooks: Dragonlance: Shadow of the Dragon Queen, Planescape: Adventures in the Multiverse, The Book of Many Things, Bigby Presents: Glory of the Giants,

[fergcb]

These features are not in the SRD, so we cannot legally add them to the API! Check out the for more info: https://5e-bits.github.io/docs/faq

[justinyates887]

Closing merge request due to SRD restrictions. (Apologies for being unaware)