Extracted `read_collections` from site.rb into reader.rb

- Extracted
  - Updated References
  - Ran Tests

Signed-off-by: Martin Jorn Rogalla <martin@martinrogalla.com>

lib/jekyll/reader.rb

@@ -180,6 +180,15 @@ module Jekyll
       end
     end
 
+    # Read in all collections specified in the configuration
+    #
+    # Returns nothing.
+    def read_collections
+      site.collections.each do |_, collection|
+        collection.read unless collection.label.eql?("data")
+      end
+    end
+
     def sanitize_filename(name)
       name.gsub!(/[^\w\s_-]+/, '')
       name.gsub!(/(^|\b\s)\s+($|\s?\b)/, '\\1\\2')

lib/jekyll/site.rb

@@ -132,16 +132,7 @@ module Jekyll
       self.layouts = LayoutReader.new(self).read
       reader.read_directories
       reader.read_data(config['data_source'])
-      read_collections
-    end
-
-    # Read in all collections specified in the configuration
-    #
-    # Returns nothing.
-    def read_collections
-      collections.each do |_, collection|
-        collection.read unless collection.label.eql?("data")
-      end
+      reader.read_collections
     end
 
     # Run each of the Generators.