startup: Blacklist incompatible mobile browsers

These user agents have been blacklisted on the mobile site for some time.

They have been re-reviewed alongside the A grade phones supported by
jQuery mobile [1] and jQuery [2]

[1] http://jquerymobile.com/gbs/
[2] http://jquery.com/browser-support/

Change-Id: If7743c476e95002174763514428c17dfcbe7da4c
Merge "startup: Blacklist incompatible mobile browsers"