As a Wikisource user, I want the title field of WS-Export to be pre-filled, so that I can easily enter in correct information related to the title (as opposed to the current manual process, which is difficult and confusing).
Background: At the moment, it's possible to specify ?lang=foo to prefill the Language form field in WSExport, but the same isn't true of the Title field. Specifying ?page=Foo in the URL results in downloading Foo.epub from the default language Wikisource (which is determined by the URL parameter or the HTTP Accept header). This means that the 'Choose format' link (e.g. from the gadget) from Wikisource doesn't pre-fill correctly, and the user has to re-enter the title of the book they want. We can use a new URL parameter (e.g. ?title=) to distinguish pre-fill from download-now, without breaking existing links.
Acceptance Criteria:
- Make it possible to pre-fill the page title field for WS-Export