improve no projects screen

* correct odd capitalization pattern in tagline
* remove "click on button" statement as telling a user to click something is not a good web development practice
* add missing period for consistency

app/views/dashboard/_zero_authorized_projects.html.haml

 %h3.page-title Welcome to GitLab!
-%p.light Self Hosted Git Management application.
+%p.light Self hosted Git management application.
 %hr
 %div
   .dashboard-intro-icon
@@ -11,9 +11,8 @@
       - if current_user.can_create_project?
         You can create up to
         %strong= pluralize(current_user.projects_limit, "project") + "."
-        Click on the button below to add a new one
       - else
-        If you are added to a project, it will be displayed here
+        If you are added to a project, it will be displayed here.
 
     - if current_user.can_create_project?
       .link_holder
@@ -29,7 +28,7 @@
       %p.slead
         You can create a group for several dependent projects.
         %br
-        Groups are the best way to manage projects and members
+        Groups are the best way to manage projects and members.
       .link_holder
         = link_to new_group_path, class: "btn btn-new" do
           New group »