py-zfec: updated to 1.5.3

Release 1.5.3:

** Fix setup.py problem that broke builds on slackware (or other systems with
  setuptools-22.0.5, which is too old to know that "name" might come from
  the setup.cfg metadata section)

Release 1.5.2:
** Add Appveyor (CI for Windows)
** Use older C syntax to appease the Windows compilers we use on Appveyor.
  The previous release just didn't compile there, which broke Tahoe builds.

Release 1.5.1:
** stop using PBR, it interacts badly with Versioneer, causing bad version
  strings like "0+unknown" after pip install

Release 1.5.0:
** Add support for python3.5/3.6/3.7
** switch to PBR for packagine
** fix unclosed-file and illegal-seek errors
** fix memory leak in fec.c
** remove unused stdeb.cfg

(adam)