added hello_world.txt
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'upstream/master'
added de4_gordon.ipynb data explor 04 python notebook
Merge pull request #23 from gorayfle/gordon_dataexplor04

Gordon dataexplor04
moved some files
Merge remote-tracking branch 'upstream/master'

Standard  update