Fixes Incorrect Sidebar Links

Functions with the same name had the same id. For example, lunr.Pipeline.load(), lunr.SortedSet.load(), lunr.Index.load(), etc., all had id='load', so every href='#load' link in the sidebar jumped to lunr.Pipeline.load(), because it was the first id='load' on the page. These changes give every identically named function a unique id, such as, #Pipeline-load, #SortedSet-load, and #Index-load, so that the sidebar behaves correctly.