Twig spaceless tag is removing whitespace padding from many elements

Problem:

During this commit, #2784463: Convert outside_in_page_(top|bottom)() to a #theme_wrappers, the {% spaceless %} tag was introduced. This tag removes all the whitespace between HTML tags. It affects to almost *all* the HTML content in the page because it is used in a template that acts as a page wrapper. This only happens *IF* the outside_in module is enabled.

The spaceless tag removes whitespace that is used to add extra padding to certain UI elements, like checkbox labels, radio labels and breadcrumbs.
See screenshot.

Solution:

Remove the spaceless tag.

Twig Documentation of spaceless tag:
http://twig.sensiolabs.org/doc/tags/spaceless.html

Patch attached in #2

TODO:

Review patch.
Review spaceless tag used in other templates in Drupal core.