chore(package): update core-js to version 2.2.0
chore(package): update core-js to version 2.2.0

http://greenkeeper.io/
Dignifiedquire/karma,panrafal/karma,kahwee/karma,kahwee/karma,wesleycho/karma,david-garcia-nete/karma,panrafal/karma,wesleycho/karma,shirish87/karma,david-garcia-nete/karma,Dignifiedquire/karma,david-garcia-nete/karma,maksimr/karma,mprobst/karma,Dignifiedquire/karma,wesleycho/karma,kahwee/karma,johnjbarton/karma,johnjbarton/karma,pedrotcaraujo/karma,karma-runner/karma,panrafal/karma,pedrotcaraujo/karma,karma-runner/karma,johnjbarton/karma,karma-runner/karma,shirish87/karma,karma-runner/karma,maksimr/karma,pedrotcaraujo/karma,maksimr/karma,wesleycho/karma,mprobst/karma,shirish87/karma,kahwee/karma,mprobst/karma,Dignifiedquire/karma,johnjbarton/karma,pedrotcaraujo/karma