replace tutorial images, close #1
Merge branch 'master' of github.com:Kathypennacchio/docs into Kathypennacchio-master
Merge branch 'Kathypennacchio-master'
imageoptim
Merge branch 'master' of github.com:CartoDB/docs

Conflicts:
	img/layout/cartodb-editor/bubble.png
	img/layout/cartodb-editor/category.png
	img/layout/cartodb-editor/choro.png
	img/layout/cartodb-editor/cluster.png
	img/layout/cartodb-editor/density.png
	img/layout/cartodb-editor/simple.png
	img/layout/cartodb-editor/torque.png