Bootstrap initial refactor
Get select2 to use bootstrap variables
Fix labels styling
Adding correct button classes. Some tables fixes
More of bootstrap refactoring in various pages
Cleanup, Cleanup, Cleanup...
More fixes and style cleaning
Filter styles cleanup
Merge branch 'bs_admin_refactor'

* bs_admin_refactor:
  Filter styles cleanup
  More fixes and style cleaning
  Cleanup, Cleanup, Cleanup...
  More of bootstrap refactoring in various pages
  Adding correct button classes. Some tables fixes
  Fix labels styling
  Get select2 to use bootstrap variables
  Bootstrap initial refactor

Conflicts:
	backend/app/assets/stylesheets/spree/backend/components/_admin_lte_overrides.scss
	backend/app/assets/stylesheets/spree/backend/components/_icons.scss
	backend/app/assets/stylesheets/spree/backend/components/_labels.scss
	backend/app/assets/stylesheets/spree/backend/components/_tables.scss
	backend/app/assets/stylesheets/spree/backend/spree_admin.css.scss
	backend/app/views/spree/admin/shared/_header.html.erb
	backend/app/views/spree/admin/shared/_order_tabs.html.erb
Fixing errors in merge
Fix table stylesheet
New pack of styles. Msotly select2 & jquery-ui styles.