base: new login and orcid templates

* Adds `accounts/login.html` template to extend the default one.

* Creates new LESS file to style the ORCID login button according
  to the official documentation and adds it to the main styles
  bundle.

* Creates the new static `orcid.hmtl` to serve as the skeleton
  page for the upcoming context.

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>
global: update site name config variable

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>
deposit: addition of deposit/index template

* Sets the collapsible panel open by default by overriding
  completely the `deposit/index.html`.

* Applies CSS styles to match the new color scheme.

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>
base: initial release of new design

* Uses semantic markup to provide better readability for crawlers.

* Adds endpoint values to url_for for header links.

* Highlights active elements based on the current blueprint.

* Removes unused code and switched "Sign in" button to redirect
  to the login form without displaying any modal.

* Adds dropdown on the user button with the option to logout.

* Makes all links translatable.

* Adds `.container` wrapper on the main body of each page to keep
  the layout consistent.

* Introduces LESS variables to customize the default Bootstrap
  look and feel.

* Redesigns breadcrumbs.

* Submit link now points to literature submission.

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>