TPAC - Remove images from login help page

Because images are hard to translate.

Signed-off-by: Thomas Berezansky <tsbere@mvlc.org>
Signed-off-by: Ben Shum <bshum@biblio.org>
Signed-off-by: Dan Scott <dan@coffeecode.net>
TPAC - new CSS for login help elements

Instead of having everything hard coded into the page, move important
pieces into the style.css.tt2.

Signed-off-by: Ben Shum <bshum@biblio.org>
Signed-off-by: Dan Scott <dan@coffeecode.net>