Pyecore

+++++++++
**Features**

- Add xmi option for default value serialization. This new option allows to
save the default value in the produced XMI, and it also gives the ability to
store attribute set to `None` as `xsi:nill="true"` field.

++++++
**Features**

- Add href uuid (de)serialization for XMI. This new features allows the XMI
for having href that directly uses the uuid of the target element.


**Bugfixes**

- Fix nsmap computation for heteroneous models with crossrefs. When crossrefs
are serialized in XMI, they need to add the referenced namespace at the
root of the XMI. This fix adds these namespace and their related prefixes.

++++++

**Bugfixes**

- Fix bad ``EAttribute`` decoding for XMI root element. By default, each field
of an XMI root were decoded as strings instead of making use of the
``from_string(...)`` method from the type of each attribute. This case is not
very common, but could still occur.

++++++

**Features**

- Add option for specific XMI "type" field serialization. XMI uses a special
field to encode the type of the element. This field is almost always named:
``xsi:type``, but in some cases, ``xmi:type`` is used instead. To deal with such
cases, an option is now available: ``XMIOptions.OPTION_USE_XMI_TYPE``.

**Bugfixes**
- Add missing 'type' field for XMI href serialization. The 'xsi:type' field is
required when a crossreference is serialized. This field is used to check if
the resolved resource has the right type (not really, but it help). This
field is kinda optional at the moment for PyEcore, but required for Java-EMF,
otherwise the EMF will not be able to create the right proxy for the
crossreferenced resource.

++++++++++++

**Features**

- Add missing ``eAllAttributes()`` method for retriving all
``eStructuralFeatures`` that are ``EAttributes``.

**Bugfixes**

- Fix issue with double notification for x..1--x..* opposite references. When a
relationship with an eOpposite involving a x..1 and a x..* relationship, in
case the x..1 was set, the x..* opposite update was doing a "double set",
thus throwing two times the notification.

+++++

**Bugfixes**

- Improve ``EClass`` dynamic modifications. The ``__init__`` method of the
``EClass`` was responsible for the registration of an 'eternal_listener'
(a listener that cannot be removed. In case the ``EClass`` instance was
created using ``__new__`` then using ``__init__`` to set some values in the
parameter, the listener was registered **after** the set of some values.
This implies that some modifications (name modification for example)
couldn't be took into account in the method that sync the python class with
the ``EClass`` instance.