Bundle a collection

 * For example,
   https://en.wikibooks.org/wiki/Wikibooks:Collections/Blender_3D:_Noob_to_Pro

   would be called as,
   ./bin/mw-ocg-bundler -p enwikibooks
                        -c Wikibooks:Collections/Blender_3D:_Noob_to_Pro

 * Simulates the Collection extension, bookcmd=render_collection

Change-Id: Ia855b35d9c69e673426bc83f8dce69f06216c7d9
Move the collection parsing into `Metabook.fromCollection`.

In the process, use the `Parsoid` class for doing parsoid requests
and resolve hrefs in a slightly more robust manner.

Also tweaked the special case for wikibooks.

Change-Id: I83366997ac5ef577ca4d28d5f033c4a7696c4b15
Merge "Bundle a collection"
Merge "Move the collection parsing into `Metabook.fromCollection`."
Merge "Suppress console output during zip."
Merge "Don't create pipes for `P.spawn` by default."
Merge "Update dependencies."