Include system info in user agent
Don't clobber a core function
Add hostname to 2fa token label
Support adding private IPs
Exit nonzero on partial failures; better errors
Consistent format for system info
Better help output overall

This commit provides suite-level help when running `linode --help`.

Additionally, descriptions of actions are provided for each Linode
utility in the output of each utility's `--help` option.
Add WebService::Linode errstr to unexpected error
Update linode wrapper tool help
Update add-ip documentation
Alias add-ip to ip-add
Release 1.1.1