typos in CH2
import pymc as mc -> pm in chapter 3 + typos
typos chapter 4
Revert "Typo and phrasing change"

This reverts commit 5ab2748a0c6c4ad0aa82b950bb9cc7b0af114706.
Merge remote-tracking branch 'upstream/master'
Update ClusteringWithGaussians.py

A typo has been corrected
Merge pull request #156 from ugurthemaster/master

Update ClusteringWithGaussians.py
chapter 6 mc -> pm
mergin cebe's work
updating readme
Update separation_plot.py

A typo has been corrected.
Merge pull request #157 from ugurthemaster/master

Update separation_plot.py
Fix typo - missing apostrophe in introduction
Chapter 1 - make Poisson code runnable again
Merge pull request #158 from georgemarrows/master

Typo + code fix to Poisson example in chapter 1
Update DarkWorldsMetric.py

Minor corrections
Merge pull request #159 from ugurthemaster/master

Update DarkWorldsMetric.py
Update SMS_behaviour.py

minor correction.
Merge pull request #160 from ugurthemaster/master

Update SMS_behaviour.py
Merge remote-tracking branch 'upstream/master'