Added documentation for PYTHONPATH environment variable.
fix deprecation warnings
Merge pull request #815 from dgorissen/patch-2

fix deprecation warnings
Corrected documentation grammar and moved it.
fixed indentation
fixed indentation
fixed pep8 errors
fixed artifact error in kmeans
fixed bugs and added unit test
fixed bugs and added unit test
removed print
added docstring to unit test
added module-level docstring for test_mem
added back TypicalMemoryError imports -_-
removed extra space
Merge pull request #809 from AlassaneNdiaye/pythonpath_documentation

Added Pythonpath documentation
Merge pull request #817 from bouthilx/mem_error

Add help to MemoryError