docs: note on android on macos (#101)
docs: note on android on macos (#101)

Signed-off-by: a8d7fdba914ec41ef6e5a65854a2b125ca0691d3@lyft.com

Description: added banner to warn people of the current limitation on MacOS
Risk Level: low
envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile