Port shared secret encryption from nucypher-core#646

Muhammad-Altabba wants to merge 10 commits into

epic-port-nucypher-core-into-tsnucypher/taco-web:epic-port-nucypher-core-into-tsfrom

140-taco-on-mobile-encryption-decryptionnucypher/taco-web:140-taco-on-mobile-encryption-decryptionCopy head branch name to clipboard