Support for parsing the vendor data associated with OFVendor messages.

src/main/java/org/openflow/protocol/OFError.java

src/main/java/org/openflow/protocol/OFVendor.java

...main/java/org/openflow/protocol/factory/BasicFactory.java

...va/org/openflow/protocol/factory/OFVendorDataFactory.java

...g/openflow/protocol/factory/OFVendorDataFactoryAware.java

...a/org/openflow/protocol/vendor/OFBasicVendorDataType.java

...in/java/org/openflow/protocol/vendor/OFBasicVendorId.java

...a/org/openflow/protocol/vendor/OFByteArrayVendorData.java

src/main/java/org/openflow/protocol/vendor/OFVendorData.java

...n/java/org/openflow/protocol/vendor/OFVendorDataType.java

src/main/java/org/openflow/protocol/vendor/OFVendorId.java

...n/java/org/openflow/vendor/nicira/OFNiciraVendorData.java

...ava/org/openflow/vendor/nicira/OFRoleReplyVendorData.java

...a/org/openflow/vendor/nicira/OFRoleRequestVendorData.java

...ain/java/org/openflow/vendor/nicira/OFRoleVendorData.java

src/test/java/org/openflow/protocol/OFErrorTest.java

src/test/java/org/openflow/protocol/OFVendorTest.java