Improve comments css

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Improve notes form UI/UX

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Remove unused css

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge branch 'ui-improvements' into 'master'

Comment UI improvements

* use tabs for preview/write comment form because its better UX
* fix paddings for comment form and unnecessary borders
* remove unused css/js
* cleanup messy comment form html