Check js/css dir specified before cleanup

closes #528
Added calcview hook for view and layout

calcview allows us to hook into the view/layout selecting function and override the view that is rendered
Merge pull request #537 from marcusgreenwood/patch-1

Added calcview hook for view and layout
Add callback to mkdir
Merge branch 'master' of github.com:1602/compound
1.1.7-2