install, and requirements pages and redirect to the new sdk
pages. Also update the "older sdks"
doc to include all version-specific sdks.
also update the robots file to disallow indexing
of the old sdk docs.
Please let me know if you have other "known issues", "resolved issues", or
"highlights".
Also, note that the installing and upgrading docs are being updated in
a different CL, so the new version is not displayed on my staging server.
BUG=1790234
Automated import of CL 147297
