Merge branch 'remove-bottom-margin-for-flash-message-on-project-home-page' into 'master'

Remove bottom margin for flash message on home page

### Flash Messages 
Remove `margin-bottom: 16px` from `.no-ssh-key-message` and `.project-limit-message`. 
This added an unnecessary margin between the notification and the content which was brought up in this issue #14797.

### Affected files:
    ./app/assets/javascripts/project.js.coffee:      $(@).parents('.no-ssh-key-message').remove()
    ./app/assets/stylesheets/pages/projects.scss:.no-ssh-key-message, .project-limit-message {
    ./app/views/shared/_no_ssh.html.haml:  .no-ssh-key-message.alert.alert-warning.hidden-xs
    ./app/assets/javascripts/user.js.coffee:    $('.hide-project-limit-message').on 'click', (e) ->
    ./app/assets/javascripts/user.js.coffee:      $(@).parents('.project-limit-message').remove()
    ./app/assets/stylesheets/pages/projects.scss:.no-ssh-key-message, .project-limit-message {
    ./app/views/shared/_project_limit.html.haml:  .project-limit-message.alert.alert-warning.hidden-xs
    ./app/views/shared/_project_limit.html.haml:      = link_to 'Remind later', '#', class: 'hide-project-limit-message alert-link'

### Screenshots:
#### Before: 
![Screen_Shot_2016-05-16_at_11.45.17_PM](/uploads/35f9db16526830e49bc302e2d00ecf7e/Screen_Shot_2016-05-16_at_11.45.17_PM.png)

#### After:
![Screen_Shot_2016-05-16_at_11.38.24_PM](/uploads/b8f9ac29b574a99c962c52028f7e61dd/Screen_Shot_2016-05-16_at_11.38.24_PM.png)


See merge request !4173

app/assets/stylesheets/pages/projects.scss

@@ -7,7 +7,7 @@
 }
 .no-ssh-key-message, .project-limit-message {
   background-color: #f28d35;
-  margin-bottom: 16px;
+  margin-bottom: 0;
 }
 .new_project,
 .edit_project {