Merge pull request Kapeli#10 from chitsaou/instance-eval-file-path

when evaluating a cheatsheet ruby script, let it know where __FILE__ is.

Author: Kapeli

lib/cheatset/dsl/context.rb

@@ -2,7 +2,7 @@ module Cheatset
   module DSL
     class Context
       def initialize(filename)
-        instance_eval(File.read(filename))
+        instance_eval(File.read(filename), File.expand_path(filename))
         @filename = filename
       end
       def generate