Add custom icons

[davyzhang]

A css approach, nicer and easier. thanks to @crkvend

Anyway to custom the tabbar's icon with my own svg file?

Nice job I went for another solution by building and extending ionicons with my own svg files but css approach seems easier as long as there’s only few icons need to be customised here’s the long thread https://forum.ionicframework.com/t/add-custom-icons/559/29