[WIP] Branch for 0.3.0

[parro-it]

This is the development branch for version 0.3.0

• Fix background text of attributed string does not work properly on High Sierra. - (Background text of attributed string does not work properly on High Sierra #101)
• Fix TextArea.getText() line ending discrepancy on Windows. - (TextArea.getText() line ending discrepancy on Windows #97)
• Make all controls methods and properties noop when native control is destroyed. - (Make all controls methods and properties noop when native control is destroyed. #75)
• Reimplements setTimeout & setInterval on top of uiTimer - (Reimplements setTimeout & setInterval on top of uiTimer #93 WIP on branch uitimer)
• Add bindings for uiTimer - (Add bindings for uiTimer #92 WIP on branch uitimer)
• macOS app bundle example should use relative paths - (macOS app bundle example should use relative paths #67)
• Add wrapping MultilineEntry - (Add wrapping MultilineEntry #85)
• Compile with the same Visual Studio version as libui - (Compile with the same Visual Studio version as libui #94)
• Implement onShouldQuit with the same semnatic as libui (return true from the cb will stop the loop) (Implement onShouldQuit with the same semnatic as libui (return true from the cb will stop the loop) #98)
• Add binding for uiAreaBeginUserWindowMove & Resize (Add binding for uiAreaBeginUserWindowMove & Resize #99)