rework performLogin to load credentials from keychain
rework performLogin to load credentials from keychain

and to return an enum of strings instead of a boolean status for more
granular reporting

StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native,StoDevX/AAO-React-Native