Changed HostingServiceHook docs versionadded entry to version 2.0.12.

Changed versionadded in docs for the new HostingServiceHook to prepare for its
release in version 2.0.12.

Testing Done:
Built docs.

Reviewed at https://reviews.reviewboard.org/r/6687/
Add the missing doc files for the draft original/patched file resources.

These were missing from the tree, but were otherwise referenced in the
documentation. This simply adds the small files pointing to the
WebAPIResource instances.
Merge branch 'release-2.0.x'