Please backport python-concurrent.futures 2.1.2-1 (universe) from quantal

Please backport python-concurrent.futures 2.1.2-1 (universe) from quantal to precise.

Reason for the backport:
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concurrent.futures are a very useful feature from python3.2
the package is a backport of this to python2
It does not exist in precise so its a pretty much zero risk backport
it runs a testsuite at build time which succeeds.

Testing:
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* precise:
[X] Package builds without modification
[X] python-concurrent.futures installs cleanly and runs

No reverse dependencies