Consolidate git/github tutorials

[yunque]

There are 2 git tutorials:
curriculum/2_data_exploration_and_analysis/git_and_github
&
curriculum/2_data_exploration_and_analysis/intro_to_git_and_python

1. Should these be consolidated into one single .md or .pynb? Or perhaps split into basics and advanced?
2. Should they be moved to curriculum/4_programming_best_practices ?

[yunque]

@jzanzig

[yunque]

NB. the git-and-github tutorial is deadlinked @ 4_programming_best_practices/reproducible-software

[yunque]

NB. the intro-to-git-and-python is also linked @ curriculum/2_data_exploration_and_analysis/README.md (need to update this reference in the future if the location changes)

[jzanzig]

The intro to git & python tutorial was part of what @avishekrk and I developed for an exec ed class. I guess the only reason it's still kickin around is to preserve that we found it most helpful to introduce the two concepts (Python and Git) together rather than independently (at least when teaching to beginners).

That being said, I think the best course of action is:

• Grab anything useful form the intro_to_git_and_python notebook and put it in the data_exploration_and_analysis README, then ditch everything under intro_to_git_and_python
• Move git_and_github tutorial to curriculum/4_programming_best_practices
• Develop any future git tutorials with the existing tutorials in mind.

[jzanzig]

O nooooo we should also incorporate the training from this year: https://github.com/DSSG2017/training/blob/master/Git%20tutorial.md