Python 2/3 Compatible Release

Release containing all the changes to enable Python 2/3 compatibility.

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In addition we have:

• A lower version limit for RPyC as they changed their netref classes cache key format.
• Native data types passed to SQLAlchemy in Python 2 since it falls over with the compatibility newint type.
• Submission now creates a temporary directory for files like runscript.sh meaning filenames can clash with other submissions and they no longer need the TemporaryNamedFile random hash in them.

Initial Release

This release is the last of the purely Python 2.7 code. After this point we are using the dual Python 2/3 compatible code base.