Separate dashboard templates from frontend templates

This allows us to use different CSS frameworks for frontend and dashboard.
Separate frontend and dashboard CSS and JS

Things explicitly shared between frontend and dashboard, in base.html:
  * jQuery

Things referenced in both respective layout.html files so as to allow
for hassle-free implementor customization of frontend and dashboard
independently:
  * js/bootstrap/bootstrap.min.js
  * js/oscar/ui.js
Add Bootstrap3
Port frontend to bootstrap 3
Use grid gutter padding for product pod price box

The the grid gutter padding was removed with .no-padding only on the main
catalogue browse page, leaving search results, recent products on detail
view and a number of other pages that have product pod lists in them with a
double padding.
Make max width wider for large devices

Bootstrap 3 recognizes a class of widths >1170px "Large devices".

Suggestion by @itbabu.
Adjust number of products per row for different viewport widths

Suggestion by @itbabu.
Contain image within its container

Suggestion by @itbabu.
Make sidebar wider for small widths so that the category tree fits

Suggestion by @itbabu
Bootstrap3 uses danger in place of bootstrap2's error
Regenerate CSS