Moved the zmBandwidth option from a cookie to global Configure:: option

In addition I'm no longer passing this option around, instead calling it
where needed.  This _might_ fix #175 as the variable is being set very early on
in bootstrap.php
Use the global zmBandwidth variable from Configure::read in the layout
Moved writing of configure options from Controller to Model.  Fixes #191.
Merge pull request #190 from kylejohnson/modern

Moved zmBandwidth option from cookie to Configure:: option.  Might fix #175
Merge pull request #193 from kylejohnson/191

Moved writing of configure options from Controller to Model. Fixes #191.
Merge remote-tracking branch 'upstream/modern' into modern