Fix unhandled range error and extend deletion timeout

Fixes a bug when attempting to access a non-existant IP from
GetIPfromPID called via the list API.

Renames the provider from faas-containerd

Updates function deletion grace period to 30s to prevent any
errors in the REST API during a long-running deletion.

Tested on Linux with the figlet function which by default takes
around 5s to delete due to its write_timeout value, the deletion
now blocks rather than throwing an error.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

pkg/provider/handlers/containers.go

@@ -60,8 +60,13 @@ func GetFunction(client *containerd.Client, name string) (Function, error) {
 			if svc.Status == "running" {
 				replicas = 1
 				f.pid = task.Pid()
+
 				// Get container IP address
-				ip, _ := GetIPfromPID(int(task.Pid()))
+				ip, getIPErr := GetIPfromPID(int(task.Pid()))
+				if getIPErr != nil {
+					return Function{}, getIPErr
+				}
+
 				f.IP = ip.String()
 			}
 		} else {