This implementation only works in JavaScript, while the Observable transpilation
story gets worked out. Right now, the service just makes a simple request,
and returns an Observable of Response.
Additional functionality will be captured in separate issues.
Fixes#2028
Limitations because of preview status (see #960):
- does not yet use ShadowDOM
- does not use a builtin conditional like `if`
- uses a temporary bower repository
Closes#943
