fix incorrectly cased hudsonURL
Switch to manifest_version 2 and conform to changes it requires.

manifest.json had to be modified because some options were obsolete.

A background page is autogenerated now so no need to have it.

Inline eventhandlers are no longer supported by default so they are
initialized in js instead.
change the event handler from onchange to oninput on check box
Workaround Chrome issue 134315 for showing desktop notification icons.

See https://code.google.com/p/chromium/issues/detail?id=134315 for details.