first release as a stand-alone module

The testing.py module has, in fact, an already pretty long history as part of the biskit package. This version has been modified from biskit.test.py (python 3 branch) so that it can be easily used in other packages.

Main changes:

• seems to work well now for both Python 2 and 3
• renamed BiskitTest to AutoTest
• copied any routines from biskit.tools into the testing module itself
• more detailed documentation
• added examplepackage and example.py
• Apache 2 license (instead of GPL 3)