add some design notes
add some design notes

jbalint/banshee-sympatico,jbalint/banshee-sympatico,jbalint/banshee-sympatico,jbalint/banshee-sympatico,jbalint/banshee-sympatico,jbalint/banshee-sympatico,jbalint/banshee-sympatico,jbalint/banshee-sympatico