The first part of the new yuph style.

Goodbye the old, welcome the new! (#partOne)

This commit affects:
* The main style pages
* The homepage layout
* The sessions' layout

ps: This commit broke the ideas' page layout
losing weight (in the browser)

Adjusting the new home assets, to be more light
Revert "losing weight (in the browser)"

This reverts commit 59dad2b8e3dd2a653f6284f122d6bbe35afa438e.
New layout part 2

* Left menu
* Sign-in
* Sign-up
* Show idea
* More some css fixes
New Layout Part (3 / 5)

Include

* Forum New
* Show Ideas
* Home Improvement
New Layout Part (4/5)

* New Ideas Layout (pt 1 - Test).

—
#missing:
* Forum
* New Idea Layout (pt .2)
Merge branch 'new-homepage'

Conflicts:
	app/assets/stylesheets/screen.css.scss
	app/views/devise/registrations/new.html.erb
	app/views/layouts/application.html.erb
	app/views/shared/_login_form.html.erb
	db/schema.rb