Handle partial results returned from a GetVolumes API call

[Ricardo-Osorio]

Handle the context deadline exceeded error from the backend (identified by the http status code PartialContent returned) and print the data we managed to get back

This data set will most likely fail to include some of the data about volume replicas so for those volumes we may see 0/2 replicas healthy even thought they may exist and be healthy

To make this clear for the user I have added a message that prints just before the table output that reads:
context deadline exceeded, these are partial results and may be missing replica states for some volumes

We expect this to be a rare case to hit

[boedy]

I've been experimenting with Ondat the last couple of weeks, but I've already hit this error message multiple times. This directly makes the CLI unusable to get or describe volumes.

➜  go-cli git:(master) ./bin/storageos describe node
Error: timed out performing command

➜  go-cli git:(master) ./bin/storageos get volumes -A
context deadline exceeded, these are partial results and may be missing replica states for some volumes
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0xa8 pc=0x13a9f78]

goroutine 1 [running]:
code.storageos.net/storageos/c2-cli/output.newDeployment(0xc000098a00, 0x14e52a0?, 0x1, {0x1514b37, 0x1b})
        /Users/boedy/scratchpad/ondat/go-cli/output/volume.go:109 +0x98
code.storageos.net/storageos/c2-cli/output.newDeployments({0xc0000c2270, 0x1, 0x1513f01?}, 0x1514b37?, 0x1b?, {0x1514b37, 0x1b})
        /Users/boedy/scratchpad/ondat/go-cli/output/volume.go:133 +0xc8
code.storageos.net/storageos/c2-cli/output.NewVolume(0xc0000f4420, {0xc00002e274, 0x4}, 0x24?)
        /Users/boedy/scratchpad/ondat/go-cli/output/volume.go:92 +0x331
code.storageos.net/storageos/c2-cli/cmd/get.(*volumeCommand).runWithCtx.func2({0xc0000e20e0, 0xd, 0xc0000f14d0?}, 0x24?, 0xc000132008?)
        /Users/boedy/scratchpad/ondat/go-cli/cmd/get/volume.go:82 +0x114
code.storageos.net/storageos/c2-cli/cmd/get.(*volumeCommand).runWithCtx(0xc0001744d0, {0x15ce808, 0xc000134d20}, 0x13a?, {0xc00021c3e0?, 0x0, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/get/volume.go:118 +0x746
code.storageos.net/storageos/c2-cli/cmd/runwrappers.AuthenticateClient.func1.1({0x15ce808, 0xc000134d20}, 0x150bb45?, {0xc00021c3e0, 0x0, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/runwrappers/runwrappers.go:88 +0x12d
code.storageos.net/storageos/c2-cli/cmd/runwrappers.EnsureTargetOrSelectors.func1.1({0x15ce808?, 0xc000134d20?}, 0x1877e80?, {0xc00021c3e0?, 0x1877e80?, 0x37e11d600?})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/runwrappers/runwrappers.go:102 +0x55
code.storageos.net/storageos/c2-cli/cmd/runwrappers.EnsureNamespaceSetWhenUseIDs.func1.1({0x15ce808, 0xc000134d20}, 0x2b233e08?, {0xc00021c3e0, 0x0, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/runwrappers/runwrappers.go:126 +0xfa
code.storageos.net/storageos/c2-cli/cmd/runwrappers.RunWithTimeout.func1.1({0x15ce7d0?, 0xc000136008?}, 0xc000167bb8?, {0xc00021c3e0, 0x0, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/runwrappers/runwrappers.go:62 +0xa7
code.storageos.net/storageos/c2-cli/cmd/runwrappers.Chain.func1.1({0x15ce7d0, 0xc000136008}, 0x4?, {0xc00021c3e0, 0x0, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/runwrappers/runwrappers.go:49 +0xa3
code.storageos.net/storageos/c2-cli/cmd/get.newVolume.func3(0xc0001c1b80?, {0xc00021c3e0, 0x0, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/cmd/get/volume.go:328 +0x1d2
github.com/spf13/cobra.(*Command).execute(0xc0001c1b80, {0xc00021c3c0, 0x1, 0x1})
        /Users/boedy/scratchpad/ondat/go-cli/vendor/github.com/spf13/cobra/command.go:826 +0x67c
github.com/spf13/cobra.(*Command).ExecuteC(0xc000147900)
        /Users/boedy/scratchpad/ondat/go-cli/vendor/github.com/spf13/cobra/command.go:914 +0x2ef
github.com/spf13/cobra.(*Command).Execute(...)
        /Users/boedy/scratchpad/ondat/go-cli/vendor/github.com/spf13/cobra/command.go:864
main.main()
        /Users/boedy/scratchpad/ondat/go-cli/main.go:50 +0x345

What's worse is that there is currently no way to resolve the issue. The faulty volumes / replica's are not visible in k8s and I can't use the cli to remove them.