Issue during unseal process

[bhavikkumar]

This occurs randomly when trying to unseal the vault. Either the issue is with Vault not knowing it is a valid key.

2017-11-07 11:14:15,406 P8256 [INFO]    {"time":"2017-11-07T11:14:15Z","level":"error","error":"Error making API request.\n\nURL: PUT http://10.0.3.36:8200/v1/sys/unseal\nCode: 400. Errors:\n\n* Unseal failed, invalid key","message":"Error during unseal process"}
2017-11-07 11:14:15,406 P8256 [INFO]    panic: runtime error: invalid memory address or nil pointer dereference
2017-11-07 11:14:15,406 P8256 [INFO]    [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x716ad5]
2017-11-07 11:14:15,406 P8256 [INFO]
2017-11-07 11:14:15,406 P8256 [INFO]    goroutine 1 [running]:
2017-11-07 11:14:15,406 P8256 [INFO]    main.UnsealVault(0xc42017e0c0, 0xc420010820, 0x5, 0x5, 0xc4200479e0)
2017-11-07 11:14:15,406 P8256 [INFO]            /home/travis/gopath/src/github.com/depost/init-vault/main.go:87 +0x55
2017-11-07 11:14:15,406 P8256 [INFO]    main.main()
2017-11-07 11:14:15,406 P8256 [INFO]            /home/travis/gopath/src/github.com/depost/init-vault/main.go:36 +0x2b4