Creates ColorChanger project to demonstrate tintColor

Sets allowed orientation and adds license headers to source files.
Adds ability to change the tint colour for the top-level view

We have a selection of UI controls to demonstrate the effect that
changing the tint colour has. Also adds a switch to control dimming.
Adds a custom control which responds to tintColor

This control isn't actually a control, but it demonstrates how tint
colour can be used in a UIView subclass.
Adds a tintable image to the demo

Really nice and simple to do!
Blog writeup for tintColor

Need to take some pictures and add them in.
Images to demonstrate the colour changes
Missing a code indent
Merge branch 'days/06-tintColor'