Creates a new installation for the given extension and user.
Installation.
Is used to represent a concrete installation.
id -- id of concrete installation. environment -- installation environment. account -- installation owner account. settings -- installation settings. events -- installed, uninstalled and updated events. status -- status of installation. comment -- reason of uninstall.
Environment.
Is used to specify a concrete Environment.
id -- the environment id. type -- the environment type: development, test or production. icon -- the environment icon.