Strictyaml

* BUGFIX PATCH : Fix the behavior of getting and deleting items on a YAML object where the key have gone through a validator.
* PATCH BUGFIX : Allow setting of properties using __setitem__ when a key validator was used.
* PATCH REFACTOR : Sequence and Mapping validators now inherit from SeqValidator and MapValidator.
* PATCH REFACTOR : Added some docstrings and removed unnecessary method.
* PATCH REFACTOR : Added docstrings and clarified variable names.
* PATCH REFACTOR : Moved YAMLPointer class into its own file.
* PATCH REFACTOR : Refactored the processing code.
* BUGFIX PATCH : Fix revalidation when using mappings that process keys.
* MINOR : FEATURE : Throw exception on inconsistent indents.
* PATCH : REFACTOR : Cleaned up stories.
* PATCH : REFACTOR : Changes to enable documentation generation.
* PATCH : REFACTOR : Upgraded hitchstory and strictyaml in hitch environment.

* MINOR : FEATURE : Optionally specify minimum_keys and maximum_keys in MapPattern.

* MINOR : FEATURE : Revalidation of code parsed with any (to make it work with scalar values).
* PATCH : REFACTOR : Renamed defer validation -> revalidation.
* MINOR : FEATURE : Revalidation of code parsed with Any.
* PATCH : REFACTOR : Added more useful YAMLChunk methods.
* PATCH : REFACTOR : Fixed type assertions.
* PATCH : FEATURE : Added assert for or validators.
* PATCH : FEATURE : Clearer error messages for non-matching scalars.
* PATCH : REFACTOR : Made linter happy.
* MINOR : FEATURE : Made clearer exception messages and prevented invalid validators from being used in compound validators.
* PATCH : REFACTOR : Reworked the way YAML objects are created.
* PATCH : REFACTOR : Reworked the way mapping, sequence, 'or' and scalar validators work.
* PATCH : REFACTOR : Add doctests to the regression suite.
* PATCH : REFACTOR : Clean up Map() class so it interacts only via chunk.process().
* PATCH : REFACTOR : Cleaned up some stories.
* PATCH : REFACTOR : Make linter happy.
* PATCH : REFACTOR : Moved more validation functionality into the chunk object.
* PATCH : REFACTOR : Clean up validator code.
* PATCH : REFACTOR : Move more core code away from validators into YAMLChunk.

* MINOR : FEATURE : Enum with item validators.
* MINOR : FEATURE : Mappings with key validators.
* MINOR : FEATURE : Key validation using Map().
* PATCH : PERFORMANCE IMPROVEMENTS : Avoided the use of deepcopy() every time a validator is used.
* MINOR BUGFIX : Roundtripping failure fixes.
* PATCH : REFACTOR : Only use chunk object in scalar validators.
* PATCH : REFACTOR : Removed dependency on two variables being fed in to the validate_scalar method.

* PERFORMANCE : Improved performance of dumping by restricting the number of times deepcopy() is called.
* FEATURE : Performance improvements.
* FEATURE : Create dumpable YAML documents from simple dicts/lists of python data.
* FEATURE : Create documents from scratch.
* FEATURE : Create YAML documents directly.
* FEATURE : Merging of YAML documents.
* BUGFIX : Handle roundtripping changing indexed elements in sequences.
* BUGFIX : Fix for scalar value roundtripping.
* FEATURE : Set sequences using lists.
* FEATURE : Use 'yes' and 'no' as default boolean values.
* FEATURE : Set nested mappings that get correctly validated using __setitem__ interface on YAML() objects.
* BUGFIX : Don't futz with the ordering of keys when setting vars via __setitem__.

* BUGFIX : Decimal point representer does not work with decimal.Decimal() object, so using float instead.
* BUGFIX : In python 2.x, the __ne__ magic method is called on != rather than negating the result of the __eq__ method. This caused undesired behavior in python 2.x.
* FEATURE : Parser errors will have the correct label attached.
* FEATURE : .data now returns ordereddicts.
* BUG : Boolean 'y' and 'n' values ought to resolve to True and False.
* BUG : Map keys were accidentally optional by default.
* BUG : Disallowed exceptions were previously not labeled.
* BUG : Duplicate key exceptions were previously not labeled.
* BUG : Fix for roundtripping multiline strings in python 2.
* FEATURE : Label parsed YAML and have the label appear in exceptions.
* BUG : Fix the way that data is roundtrip loaded into the yaml object via __setitem__.
* BUG : Fixed roundtripping without using load()