* Nothing needs the arrows for input, especially 2FA

* Moved into LESS

New CSS linter which is much more powerfull than the previous one.
Configuration is default but I had to remove a few rules that were
throwing too many or weird errors.

More importantly, the linter will exit with code 1 on errors so now our
build will fail if the CSS linter fails which should eliminate linter
errors being introduced without notice.

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Add lang specific font stacks

* Force font changes

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Fix icons

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Fix octicons and icons

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Just override the semantic ui fonts only

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Missed the headers... override them too

* Missed some more semantic ui stuff

* Fix PT Sans

Signed-off-by: Andrew Thornton <art27@cantab.net>

* More changes

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Squashed commit of the following:

commit 7d1679e907
Author: Mike L <cl.jeremy@qq.com>
Date:   Wed Mar 13 13:53:49 2019 +0100

    Remove missed YaHei leftover from _home.less

commit 0079121ea9
Author: Mike L <cl.jeremy@qq.com>
Date:   Wed Mar 13 12:03:54 2019 +0100

    Fix overdone fixes (inherit, :lang)

commit 62c9199159
Author: Mike L <cl.jeremy@qq.com>
Date:   Wed Mar 13 02:29:10 2019 +0100

    Fix elements w/ explicit lang (language chooser)

commit b3117587aa
Author: Mike L <cl.jeremy@qq.com>
Date:   Tue Mar 12 20:17:26 2019 +0100

    Fix textarea also (to match body)

commit 81cedf2c30
Author: Mike L <cl.jeremy@qq.com>
Date:   Tue Mar 12 19:41:39 2019 +0100

    Revert css temporarily to fix conflict

commit 80ff82797f
Author: Mike L <cl.jeremy@qq.com>
Date:   Tue Mar 12 19:15:30 2019 +0100

    Tweak CJK, fix Yu Gothic, more monospace inherits

commit 581dceb9a8
Author: Mike L <cl.jeremy@qq.com>
Date:   Mon Mar 11 13:09:26 2019 +0100

    Add Lato for latin extd. & cyrillic, improve CJK

* update stylesheet

* Add autoprefixer to css build

* also use autoprefixer on theme files

* reset to master

* build css

* Fixed spacing

* Viewport meta tag

* responsive: dashboard

* responsive: issues page

* responsive: Explore page

* responsive: navbar, and some navbar css refactoring

* responsive: button for collapsing navbar in mobile view

* Mark the hamburger button as active when pressed

* better homepage for responsive views

* Bring back jump class in navbar

The class was necessary, because this way the
dropdown doesn't assume the contents of the
selected item.

* make repository homes responsive

* Make file view page responsive

* Make forms look good on responsive views

* make commits and commit diff view responsive

* issues and PRs

* responsive wiki

* Don't place auto-init far off the page

* Minor changes to amend broken stuff

minor improvements

- make login/sign up in navbar stackable
- make navbar in explore and sign in not stackable

Change selected class in TestPullCompare

Fix typo that happened when rebasing

fix dashboard on org view

improve profile UI

Use clearing on file diff to fix broken UI caused by floating elements

remove unresolved merge conflict, and | Sanitize

Fix repo home not loading

* add google+

* sort signin oauth2 providers based on the name so order is always the same

* update auth tip for google+

* add gitlab provider

* add bitbucket provider (and some go fmt)

* add twitter provider

* add facebook provider

* add dropbox provider

* add openid connect provider incl. new format of tips section in "Add New Source"

* lower the amount of disk storage for each session to prevent issues while building cross platform (and disk overflow)

* imports according to goimport and code style

* make it possible to set custom urls to gitlab and github provider (only these could have a different host)

* split up oauth2 into multiple files

* small typo in comment

* fix indention

* fix indentation

* fix new line before external import

* fix layout of signin part

* update "broken" dependency

This does not change any content and generated gogs.css is still the same.

- #1496: fallback plain text
- #1002: add date header
- #913: fix encoding of header