Use concord to cleanup mutation context

lib/mutant/context.rb

@@ -1,26 +1,18 @@
 module Mutant
   # An abstract context where mutations can be appied to.
   class Context
-    include Adamantium::Flat, AbstractType
+    include Adamantium::Flat, AbstractType, Concord::Public.new(:source_path)
 
     # Return root ast node
     #
-    # @param [Rubnius::AST::Node] node
+    # @param [Parser::AST::Node] node
     #
-    # @return [Rubinis::AST::Node]
+    # @return [Parser::AST::Node]
     #
     # @api private
     #
     abstract_method :root
 
-    # Return source path
-    #
-    # @return [String]
-    #
-    # @api private
-    #
-    attr_reader :source_path
-
     # Return identification
     #
     # @return [String]
@@ -29,18 +21,5 @@ module Mutant
     #
     abstract_method :identification
 
-  private
-
-    # Initialize context
-    #
-    # @param [String] source_path
-    #
-    # @return [undefined]
-    #
-    # @api private
-    #
-    def initialize(source_path)
-      @source_path = source_path
-    end
   end # Context
 end # Mutant