Rationalising more of EIEIO.

The AbstractEIEIOMessage class was not in widespread use, and actually
needed to be subclassed to be used at all, so renaming it (and getting
rid of the directory that it was in) is very low impact.

spinnman/connections/abstract_classes/eieio_sender.py

@@ -17,7 +17,7 @@ def send_eieio_message(self, eieio_message):
 
         :param eieio_message: The eieio message to be sent
         :type eieio_message: \
-                    :py:class:`spinnman.messages.eieio.abstract_messages.abstract_eieio_message.AbstractEIEIOMessage`
+                :py:class:`spinnman.messages.eieio.eieio_message.EIEIOMessage`
         :raise spinnman.exceptions.SpinnmanIOException: If there is an error\
-                    sending the message
+                sending the message
         """

spinnman/messages/eieio/__init__.py

@@ -1,7 +1,8 @@
+from .eieio_message import EIEIOMessage
 from .eieio_prefix import EIEIOPrefix
 from .eieio_type import EIEIOType
 from .create_eieio_command import read_eieio_command_message
 from .create_eieio_data import read_eieio_data_message
 
-__all__ = ["EIEIOPrefix", "EIEIOType", "read_eieio_command_message",
-           "read_eieio_data_message"]
+__all__ = ["EIEIOMessage", "EIEIOPrefix", "EIEIOType",
+           "read_eieio_command_message", "read_eieio_data_message"]

spinnman/messages/eieio/command_messages/eieio_command_message.py

@@ -1,7 +1,7 @@
-from spinnman.messages.eieio.abstract_messages import AbstractEIEIOMessage
+from spinnman.messages.eieio import EIEIOMessage
 
 
-class EIEIOCommandMessage(AbstractEIEIOMessage):
+class EIEIOCommandMessage(EIEIOMessage):
     """ An EIEIO command message
     """
     __slots__ = [

spinnman/messages/eieio/data_messages/eieio_data_message.py

@@ -1,7 +1,6 @@
 from spinnman.exceptions import SpinnmanInvalidPacketException,\
     SpinnmanInvalidParameterException
-from spinnman.messages.eieio.abstract_messages import AbstractEIEIOMessage
-from spinnman.messages.eieio import EIEIOType, EIEIOPrefix
+from spinnman.messages.eieio import EIEIOMessage, EIEIOType, EIEIOPrefix
 from spinnman.constants import UDP_MESSAGE_MAX_SIZE
 from .eieio_data_header import EIEIODataHeader
 from .key_data_element import KeyDataElement
@@ -16,7 +15,7 @@
 _TWO_WORDS = struct.Struct("<II")
 
 
-class EIEIODataMessage(AbstractEIEIOMessage):
+class EIEIODataMessage(EIEIOMessage):
     """ An EIEIO Data message
     """
     __slots__ = [

spinnman/messages/eieio/eieio_message.py

@@ -0,0 +1,5 @@
+class EIEIOMessage(object):
+    """ Marker interface for an EIEIO message
+    """
+
+    __slots__ = ()