PBL-21894 Add color support for window layout editor

[Spacerat]

This PR adds full support for colours to the Interface Builder, with fallbacks supported for B/W watches.

[Katharine]

I question your sense of colour.

[Katharine]

Camel case in the UI editor.

[Spacerat]

OK, I've changed it everywhere

[Katharine]

This has merge conflicts.

[Spacerat]

Conflicts fixed!

[Katharine]

Move this inside the anonymous function (as the first statement).

[Katharine]

The appearance of ActionBarLayer should be updated to match its 3.x appearance (a 30-pixel-wide bar down the side; you'll have to check icon positioning).

[Spacerat]

Would you want to that to change depending on whether the user is working with 2.x or 3.x?

[Katharine]

Yes.

[Spacerat]

Hmm, looking at it, it seems I never actually added anything to disable the colour features when making a 2.x project...

[Spacerat]

OK, I've fixed the code issues, the ActionBarLayer display, and made the colour options SDK 3 only

[Katharine]

I wonder if the various other globals you've added (IB.Settings, IB.ColourEnabled) should also be settings, colourEnabled, etc.?

[Spacerat]

IB.Settings is a submodule like ResourceManager/etc. ColourEnabled I wasn't sure about, since it's effectively a constant for the lifetime of the page.

[Katharine]

if(constant) never makes sense; lets change that one.

[Spacerat]

Right, PBIs will work in the ActionBarLayer now, and I renamed ColourEnabled to colourEnabled.

[Katharine]

This should probably just be called gcolour.