extra spaces removed?
renamed ols lesson Residuals
created Least_Squares_Estimation lesson based on Brian's lecture
new residuals variation lesson to explain r^2 based on brian's lecture
fixed up lesson on residual variation
fixed problems with residual variation lesson and added dependson.txt file to least square lesson
added ANY_of_exprs to residual variation lesson
more lesson fixes, removed dependson.txt in LSE lesson and put conditional in initLesson to load different demo files (with and without manipulate) depending on if they're using RStudio or not.
implemented 2 of Birone's suggestions in lse lesson
conflict removed (fixed manifest)

Merge remote-tracking branch 'kuiper/master'

Conflicts:
	Regression_Models/MANIFEST