adding failing deepcopy wavform tests

see #689
correcting deepcopy support for segy traces

see #689
* updating corresponding test that it runs with most waveform plugins
* converting prints to warnings
more verbosity through unittests longMessag format

see #689
* adding longMessag format (for python > 2.7), which will give us more
  verbosity in error messages
robuster locating current execution directory

* reverting to more reliable way to get current execution directory
* things like
  `python -c 'import setuptools; execfile("setup.py")' clean --all develop`
  work again
* plus flake8
Merge remote-tracking branch 'mbyt/689' into releases

+ changelog, closes #689, thanks for fixing @mbyt
Merge remote-tracking branch 'upstream/releases'

Conflicts:
	CHANGELOG.txt