Use a default auri label instead of http:// urls

Use a default auri label instead of http:// urls

Use a default auri label in search results and record summary
pages. This is mostly to prevent the symptoms of LP 918020
but may be more generally useful as well.

Also, use css_button class for BibTemplate-generated auri links
in a record summary.

Signed-off-by: Jeff Godin <jgodin@tadl.org>