RFC0027 Enable "update-route", "create-route", "map-route", "routes", "route", "apps" & "app" to manage generic per-route options

[Dariquest]

CLI Support for Generic Per-Route Options

Introducing a new cli command 'update-route', which allows updates to route resources.
Extending the API of the Route to contain per route options and particularly the first one called "loadbalancing", containing a load balancing algorithm of a route.

Existing commands "create-route", "map-route", "routes", "route", "apps", "app" were also extended to accept and output the per-route options.

Detailed specification including that of for all the involved components is provided in the RFC

$ cf update-route -h
NAME:
   update-route - Update an existing route.

USAGE:
   cf update-route DOMAIN [--hostname HOSTNAME] [--path PATH] [--option OPTION=VALUE] [--remove-option OPTION]

EXAMPLES:
   cf update-route example.com -o loadbalancing=round-robin
   cf update-route example.com -o loadbalancing=least-connection
   cf update-route example.com -r loadbalancing

OPTIONS:
   --hostname, -n      Hostname for the HTTP route (required for shared domains)
   --path              Path for the HTTP route
   --option -o         Set the value of a per-route option, key-value pairs, repeat to set multiple options
   --remove-option -r  Unset a previously set option

SEE ALSO:
   create-route, map-route, routes, unmap-route

It is possible to provide options in the create-route and map-route commands.

EXAMPLES:
  cf create-route my-space example.com -o loadbalancing=round-robin
  cf map-route my-app example.com -o loadbalancing=least-connection

Why Is This PR Valuable?

Allow users to manage per-route options via the CLI instead of having to talk to the API directly.

Applicable Issues

GitHub Issue

How Urgent Is The Change?

No urgency