Support NSToolbar and Document Windows

[kolpanic]

These changes support:

• NSToolbar (with a standard-height title-bar) — toolbar heights are empirically derived for various modes; there appears to be no API for this info;
• Document windows — the calculations for positioning the various title-bar elements were incorrect for versioned documents; in particular, the Versions standard window button (and associated dash) should only affect the title's width, not it's x-position.

[indragiek]

Sorry for the delay, I'll be reviewing this in a day or two :)

[indragiek]

Just a few comments (mostly style related things). Thanks for the contribution, and sorry for the delay in reviewing.

[kolpanic]

@indragiek @jakepetroules I've fixed the style issues you noted.

@jakepetroules If you have the code to calculate the toolbar height, I'd be glad to incorporate it. Thanks.

[jakepetroules]

@kolpanic It's probably easier if we just merge your changes as-is and I can just add the calculation code afterwards.

[kolpanic]

@indragiek @jakepetroules In that case, I'll leave the toolbarHeight method as-is.

[jakepetroules]

Sounds good. I'll prepare my changes after @indragiek gets this merged.

[indragiek]

@kolpanic Thanks, merged :)

@jakepetroules Feel free to open another PR for the calculation code now. While you're at it, could you reformat INAppStoreWindow.m? This PR used spaces instead of tabs. I know you mentioned that we should consider switching to spaces altogether but that's a separate discussion, so tabs are good for now.

[indragiek]

@jakepetroules Never mind, I fixed the formatting.