added PCA walkthrough
Merge branch 'master' of github.com:patwmcnamara/GADS11-NYC-Summer2014
edited PCA walkthrough
updated lab.
Merge branch 'master' of github.com:patwmcnamara/GADS11-NYC-Summer2014
rename lesson14 folder
restore my numpy Lab solutions that got deleted.
added diagnostics & imputation labs
Merge branch 'master' of https://github.com/patwmcnamara/GADS11-NYC-Summer2014
added lab 12 and lab 13 work
Merge pull request #75 from seanpquig/squigley_class13

added lab 12 and lab 13 work
Merge branch 'master' of github.com:patwmcnamara/GADS11-NYC-Summer2014