Fix usage of Google branding watermark on search field

* Remove google_cse.css; this is no longer necessary now that we
are using Google's branding script.

* Set search field's value field after form submission.

* Use new search button icon.
Fix search results rendering bug

* Doh, the line height was creating clipping issues...
Fix styling issues with search input field

Safari was overriding our styling when the input field was
declared as type 'search'.

* style.css: Move contact_form specific declarations into global
space (site-wide); this takes care of ugly text field text edits
starting too far to the left.
Fix contact form validation issue

I had fogotten to disable validation of the phone extension
when disabling the form field.