Consolidate Casual Packages

Consolidate current Casual packages into a smaller set of packages. Proposal discussed in #50 - [x] Change MELPA redirect for casual - [x] Reorg EditKit Dependencies (cancelled) - [x] Create Casual Package - [x] agenda - [x] bookmarks - [x] calc - [x] dired - [x] editkit - [x] ibuffer - [x] info - [x] isearch - [x] lib - [x] re-builder - [x] Update Documentation - [x] Clean up migrated file headers (in progress) - [x] Implement migration logic - [x] Refactor 3rd party support in EditKit - [x] Add Migration Warnings - [x] Refactor Non-Builtin Packages - [x] avy - [x] symbol-overlay - [x] suite - [x] MELPA Review - [x] Publish Migration Warnings - [ ] ELPA Review - [ ] Remove MELPA Recipes