* Pass workspace owner email address to provisioner
* Remove owner_email and owner_username fields from agent metadata
* Add Git environment variables to example templates
* Remove "owner_name" field from provisioner metadata, use username instead
* Remove Git configuration from most templates, add documentation
* Proofreading/typo fixes from @mafredri
* Update example templates to latest version of terraform-provider-coder
- make default template max TTL 24 hours (still less than 168)
- make default workspace autostop 2 hours unless specified otherwise
- add instance type selector to aws templates
* Changes all public-facing codersdk types to use a plain int64 (milliseconds) instead of time.Duration.
* Makes autostart_schedule a *string as it may not be present.
* Adds a utils/ptr package with some useful methods.
