minor
Merge branch 'ido'
sudoku generator
fixed a bug in 'unwrap'
added a method alias: exe_cmd
implemented that a method is generated for all commands even when no body is given
updated the graph example
removed unnecessary parens
moved birthday to alloy_sample/toys; added a unit test for it
trimmed trailing spaces
added 'merge' method to represent ++
fixed arby_dsl to pass :parent_module option when appropriate; deleted old birthday.rb
tidied up file_system test
Merge branch 'master' into ido
added extra tests