nil dereference in `scw rename`

[Manfred Touron]

➜  ~  scw -D rename desperate-boyd test
DEBU[0000] curl -X PATCH -d "{\"name\":\"test\"}" -H "Content-Type: application/json" -H "User-Agent: scw/v1.7.1+dev" -H "X-Auth-Token: 00000000-0000-1000-0000-000000000000" https://api.scaleway.com/servers/11111111-1111-1111-1111-111111111111
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xb code=0x1 addr=0x0 pc=0x10c02c]

goroutine 1 [running]:
github.com/scaleway/scaleway-cli/pkg/commands.RunRename(0x8a06e0, 0xc82002c008, 0x8a01c0, 0xc82002c010, 0x8a01c0, 0xc82002c018, 0xc820097000, 0x3a, 0x3a, 0xc82000a120, ...)
    /Users/moul/go/src/github.com/scaleway/scaleway-cli/pkg/commands/rename.go:32 +0x2bc
github.com/scaleway/scaleway-cli/pkg/cli.runRename(0x75b680, 0xc82000a120, 0x2, 0x2, 0x0, 0x0)
    /Users/moul/go/src/github.com/scaleway/scaleway-cli/pkg/cli/cmd_rename.go:36 +0x19b
github.com/scaleway/scaleway-cli/pkg/cli.Start(0xc82000a100, 0x4, 0x4, 0xc8200d9140, 0x0, 0x0, 0x0)
    /Users/moul/go/src/github.com/scaleway/scaleway-cli/pkg/cli/main.go:127 +0xcf5
main.main()
    /Users/moul/go/src/github.com/scaleway/scaleway-cli/cmd/scw/main.go:19 +0x8e

goroutine 17 [syscall, locked to thread]:
runtime.goexit()
    /usr/local/Cellar/go/1.5.3/libexec/src/runtime/asm_amd64.s:1721 +0x1

goroutine 5 [syscall]:
os/signal.loop()
    /usr/local/Cellar/go/1.5.3/libexec/src/os/signal/signal_unix.go:22 +0x18
created by os/signal.init.1
    /usr/local/Cellar/go/1.5.3/libexec/src/os/signal/signal_unix.go:28 +0x37

goroutine 15 [IO wait]:
net.runtime_pollWait(0x8a20f0, 0x72, 0xc820012200)
    /usr/local/Cellar/go/1.5.3/libexec/src/runtime/netpoll.go:157 +0x60
net.(*pollDesc).Wait(0xc82017a530, 0x72, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/fd_poll_runtime.go:73 +0x3a
net.(*pollDesc).WaitRead(0xc82017a530, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/fd_poll_runtime.go:78 +0x36
net.(*netFD).Read(0xc82017a4d0, 0xc8200c0000, 0x1000, 0x1000, 0x0, 0x89c050, 0xc820012200)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/fd_unix.go:232 +0x23a
net.(*conn).Read(0xc82002c3a8, 0xc8200c0000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/net.go:172 +0xe4
crypto/tls.(*block).readFromUntil(0xc820147a10, 0x8a21b0, 0xc82002c3a8, 0x5, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/crypto/tls/conn.go:455 +0xcc
crypto/tls.(*Conn).readRecord(0xc82013b080, 0x5d6317, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/crypto/tls/conn.go:540 +0x2d1
crypto/tls.(*Conn).Read(0xc82013b080, 0xc82019d000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/crypto/tls/conn.go:901 +0x167
net/http.noteEOFReader.Read(0x8afef0, 0xc82013b080, 0xc8200143c8, 0xc82019d000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/http/transport.go:1370 +0x67
net/http.(*noteEOFReader).Read(0xc82030e180, 0xc82019d000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    <autogenerated>:126 +0xd0
bufio.(*Reader).fill(0xc82029e4e0)
    /usr/local/Cellar/go/1.5.3/libexec/src/bufio/bufio.go:97 +0x1e9
bufio.(*Reader).Peek(0xc82029e4e0, 0x1, 0x0, 0x0, 0x0, 0x0, 0x0)
    /usr/local/Cellar/go/1.5.3/libexec/src/bufio/bufio.go:132 +0xcc
net/http.(*persistConn).readLoop(0xc820014370)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/http/transport.go:876 +0xf7
created by net/http.(*Transport).dialConn
    /usr/local/Cellar/go/1.5.3/libexec/src/net/http/transport.go:685 +0xc78

goroutine 16 [select]:
net/http.(*persistConn).writeLoop(0xc820014370)
    /usr/local/Cellar/go/1.5.3/libexec/src/net/http/transport.go:1009 +0x40c
created by net/http.(*Transport).dialConn
    /usr/local/Cellar/go/1.5.3/libexec/src/net/http/transport.go:686 +0xc9d