Better explanation for import url

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

app/views/projects/new.html.haml

@@ -23,6 +23,7 @@
           .col-sm-2
           .col-sm-10
             = link_to "#", class: 'js-toggle-button' do
+              %i.icon-edit
               %span Customize repository name?
         .js-toggle-content.hide
           .form-group
@@ -46,8 +47,10 @@
               %span Import existing repo
             .col-sm-10
               = f.text_field :import_url, class: 'form-control', placeholder: 'https://github.com/randx/six.git'
-              .light
-                URL must be cloneable
+              %p.help-block
+                This url must be publicly accessible or you can add a username and password like this: https://username:password@gitlab.com/company/project.git.
+                %br
+                Import timeout is 2 minutes. For big repositories use clone/push combination.
       %hr
 
       .form-group