Viewport tagging, Responsiveness tagging, Column tagging,

* Various viewports (lte) are now tagged on html element (0, 479, 719,
959, 1199, 1439)
* Column tagging; nxs-column-1-4, 2-4, etc.
* Combined can be used to clear certain columns for certain dimensions
by the CSS
* Valign and height setting no longer occurs for resolutions <= 959
pixels (currently hardcoded in CSS) if responsiveness is turned on