Unused imports
New @NOTIFICATION_ACTION event tracking interaction time and clicked button
Handle push token update for same version-code application updates

Updating an application while keeping the same version-code often
happens during development, and in such conditions, registration ids
may become invalid.
The previous implementation did not refresh the push token in such case,
leading to expired tokens after a few weeks, only affecting the
developers.
Send push token in updateInstallationCoreProperties()

Only use a separate call whenever getting a new push token.
SDK initialization inside Application

Permits more correct tracking of opened and foreground activities on
Android 4+.
Automatically open notifications while in-app