Indexing & Enhanced Searching

• Added indexing for increased performance over large lists
  • Added Fuse.createIndex, which created and returns an index. This function can be used to pre-generate the index, which you can then save, and ultimately pass to the Fuse instance.
• Breaking changes:
  • Removed id option
  • Changed format of the search results
  • Updated TypeScript definitions
• A couple of fixes, courtesy of Daniel Dickinson:
  • Generate multiple targets with webpack (#359)
  • Fixed TypeError (#360)