Move jade files to docs/jade/

Gruntfile.js

@@ -290,8 +290,8 @@ module.exports = function (grunt) {
           }
         },
         files: {
-          'docs/_includes/customizer-variables.html': 'docs/customizer-variables.jade',
-          'docs/_includes/nav-customize.html': 'docs/customizer-nav.jade'
+          'docs/_includes/customizer-variables.html': 'docs/jade/customizer-variables.jade',
+          'docs/_includes/nav-customize.html': 'docs/jade/customizer-nav.jade'
         }
       }
     },

_config.yml

@@ -14,7 +14,9 @@ baseurl:          /
 url:              http://localhost:9001
 encoding:         UTF-8
 
-exclude:          ["vendor"]
+exclude:
+  - "jade"
+  - "vendor"
 
 # Custom vars
 current_version:  3.1.0