Load embedded OPAC via SSL by default, w/ override option

Load embedded OPAC via SSL by default, w/ override option

* url_prefix option for using/forcing SSL.
* oils.secure_opac preference for doing such with the embedded OPAC

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To use the preference, you may want to include something like this in server/skin/custom.js:

// Force non-SSL for the OPAC
try {
    netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");
    var prefs = Components.classes['@mozilla.org/preferences-service;1'].getService(Components.interfaces['nsIPrefBranch']);
    if (!prefs.prefHasUserValue('oils.secure_opac')) {
        prefs.setBoolPref('oils.secure_opac',false);
    }
} catch(E) {
    alert('Error in custom.js trying to set oils.secure_opac preference to false: ' + E + '\n');
}

Signed-off-by: Jason Etheridge <jason@esilibrary.com>
Signed-off-by: Bill Erickson <berick@esilibrary.com>