docs: Fixing redirect file

Devsite handles "redirect this directory tree" differently than DAC
did; as a result, a bunch of redirects were broken. (On Devsite, a
redirect ending in a slash redirects *only* paths that match it;
to redirect that directory and all its contents, end with /...)

Also deleted one redirect that wouldn't work (trying to redirect
foo.html#bar , which wouldn't work--the anchors are ignored on
devsite and there was a separate redirect for just foo.html).

When a redirect pointed *to* a path ending in slash -- but was clearly
meant to point to the directory itself (i.e. the /index.html file) --
I removed the trailing slash.

Redirects staged to https://android-dot-devsite.googleplex.com , so
they should all work there.

bug: 30748799
Change-Id: I6d090de5e6efa6ddb2bbe3e99fdbfb0ae02b88d5