allow hide/show of Header Text in Customizer

fix regression introduced in
http://core.trac.wordpress.org/changeset/23572, allow hide/show of
Header Text in Customizer.

Fixes http://core.trac.wordpress.org/ticket/23600.

Also remove another !important -- and there was much rejoicing.

Props SergeyBiryukov and obenland.
update post author comment markup and styles, improving hCard data parsing and simplifying styles.

http://core.trac.wordpress.org/ticket/23128
load our special Google Font in the visual editor to improve user experience.

Closes
http://core.trac.wordpress.org/ticket/22499

See also
http://core.trac.wordpress.org/changeset/23672
improve Appearance > Header styles to match front end view better -- including loading special Google Font there.

http://core.trac.wordpress.org/ticket/23790