Fixed compiler issues

- Fixed compiler error when not TargetCocoa.
- Removed unused vars and method params.
Converted EditField, StaticText to modern equivalents
Updates version to 126
Adds CFAttributedString and CFMutableAttributedString and makes CoreText methods depend on these CF types instead of NS types.
Fixes handling of empty lines in CTLine example
Core Text: Fixes small issues and adds setting of Font
Fixed compiler issues

- Fixed compiler error when not TargetCocoa.
- Removed unused vars and method params.
Converted EditField, StaticText to modern equivalents
Updates version to 126
Adds CFAttributedString and CFMutableAttributedString and makes CoreText methods depend on these CF types instead of NS types.
Fixes handling of empty lines in CTLine example
Core Text: Fixes small issues and adds setting of Font
Remove NSFont.ConvertFontToHaveTrait; this method properly belongs in NSFontManager, which does have such a method.
Add an example demonstrating how to load the application icon into an NSImage, and how to draw that NSImage into an Rb Graphics object.
Add to release notes; increment version to 127.