Implements the main functionality:
- Access bookshelves from within the workbench
- Search by spell name, tier, element and type
- Sort by tier, element or alphabetically, ascending or descending
- Three-way shift-clicking support
- Automatic return of books to bookshelves when wand is removed
I may have got a bit behind with version control. A lot behind, in fact. Maybe I'll go back and split this sometime - then again, I probably won't. But hey, at least it's here!