[IMP] web client refactoring: action and view manager

[IMP] web client refactoring: action and view manager

large rewrite of action manager, view manager and
viewmanageraction.  The goal is to lay the foundation
for the redesign of the advanced search view.

This commit includes:
* improvements to the display order (no/less flickering)
* large simplification of the breadcrumbs code
* much better html layout for the header (no table)
* bootstrapisation of the view manager
* lots of optimizations/simplification
* a base.css.map, courtesy of the last sass version