__no_hashnav_redirect exclusion + added "email" icons

Added an exclusion to the recently added auto hashnav redirect logic in
the Module Controller role to check for the query string param
'__no_hashnav_redirect'. This allows special places, like modules that
use iframes, to escape from this auto logic (see AppMimeIframe which has
also been updated to use the new feature)

Also added e-mail icons to the built-in assets (ra-icon-email(s))