add data-page property to all pages

app/views/layouts/navless.html.haml

 !!! 5
 %html{ lang: "en"}
   = render "layouts/head", title: @title
-  %body{class: "#{app_theme} application"}
+  %body{class: "#{app_theme} application", :'data-page' => body_data_page}
     = render "layouts/head_panel", title: @title
     = render "layouts/flash"
 

app/views/layouts/public.html.haml

 !!! 5
 %html{ lang: "en"}
   = render "layouts/head", title: "Public Projects"
-  %body{class: "#{app_theme} application"}
+  %body{class: "#{app_theme} application", :'data-page' => body_data_page}
     - if current_user
       = render "layouts/head_panel", title: "Public Projects"
     - else

app/views/layouts/search.html.haml

 !!! 5
 %html{ lang: "en"}
   = render "layouts/head", title: "Search"
-  %body{class: "#{app_theme} application"}
+  %body{class: "#{app_theme} application", :'data-page' => body_data_page}
     = render "layouts/head_panel", title: "Search"
     = render "layouts/flash"
 

app/views/layouts/snippets.html.haml

 !!! 5
 %html{ lang: "en"}
   = render "layouts/head", title: "Snipepts"
-  %body{class: "#{app_theme} application"}
+  %body{class: "#{app_theme} application", :'data-page' => body_data_page}}
     = render "layouts/head_panel", title: "Snippets"
     = render "layouts/flash"
     %nav.main-nav