Clean up and re-style AlgomaU's OPAC templates.

Clean up and re-style AlgomaU's OPAC templates.

In addition to adding the same graphical header so that the OPAC
more closely resembles the new Wishart website, this change
incorporates several smaller fixes:
    * replace the AlgomaU "small university/big education" logo
      with the small AlgomaU wordmark
    * center the logo via CSS, not <center>
    * fix vertical centering of the "your account log in" text --
      needs margins only left & right, not on all 4 sides
    * replace border on the user/pass input boxen so that they
      are visible once again.

Signed-off-by: Rick Scott <rick@shadowspar.dyndns.org>