upgrade blockstack.js to 0.3.3
upgrade blockstack.js to 0.3.3

blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-portal,blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-browser