readme updated with build status badges.
readme updated with build status badges.


danwalmsley/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,danwalmsley/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit