[Vue Rewrite] Start Vuex store

[devlinjunker]

Related to #748

Follows #1998

Start Adding Vuex Store

• Add separate files for folder/feed state
• Update Types and Linting
• Use computed state for SideBar items

Testing Completed

• Verified that App Builds with make
  • Verified that Admin Settings Page Loads on localhost (NC 25)
  • Verified that App loads on localhost (NC 25)
• Verified that Jest Unit Tests Pass (npm run test)
  • Added Unit Tests for Store Files
  • Added Unit tests for computed state to SideBar spec file
• Verified that linting passes (npm run lint/stylelint)
• Verified that Folder can be added/deleted and appears/disappears from side bar in UI

Up Next

• Template Testing (WIP at devlinjunker/news@vuex-store...devlinjunker:vue-template-tests)
• Add Proper Routing (WIP at devlinjunker/news@vuex-store...devlinjunker:start-routes)
• More UI Components to match current features!
• Eventually... Clean up old code