Flag Binding Refactor
Flag Binding Refactor

This patch alters the way flags are handled to coincide with the
documentation on the Viper README. The documentation indicated that flag
bindings were late, when in fact they were very, very early. This patch
changes flag bindings to behave as late bindings.

istio/viper,spf13/viper,akutz/viper,dvln/viper,ishidawataru/viper,vasu1124/viper,samt42/viper