fix(cmd): Don't crash when paratime tx submitted without paratime set

[kostko]

Fixes #62

[matevz]

Using 6dbb2a5 I'm getting a similar crash for tx show. This may require a fix in oasis-sdk :/

oasis tx show testtx2.json --network mainnet  --no-paratime
Hash: 3013be1ba6e1ef17921382f01b53f519174b2f35753d1fc37ad11bfc382f51f5
Signer(s):
  1. NcPzNW3YU2T+ugNUtUWtoQnRvbOL9dYSaBfbjHLP1pE=
     (signature: mxOARaaRkHrHiUObGO2KbUXZhmbIS2h3hsRM+3Y/DzvMtbVdwcZm2EZ7oP7dR5XHKkrQnjMwZnkT0mdZUsLIBw==)
     [INVALID SIGNATURE]
Content:
  Format: plain
  Method: accounts.Transfer
  Body:
    To: test:bob (oasis1qrydpazemvuwtnp3efm7vmfvg3tde044qg6cxwzx)
    Amount: panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0xafb0b4]

goroutine 1 [running]:
github.com/oasisprotocol/oasis-sdk/client-sdk/go/config.(*ParaTime).GetDenominationInfo(...)
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/config/paratime.go:157
github.com/oasisprotocol/oasis-sdk/client-sdk/go/types.(*BaseUnits).PrettyPrint(0xc0001b56f0, {0x13f9040?, 0xc0001ee600?}, {0xa?, 0xc0001b56b0?}, {0x13f1520, 0xc000014018})
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/types/token.go:73 +0x94
github.com/oasisprotocol/oasis-sdk/client-sdk/go/types.PrettyPrintToAmount({0x13f9040, 0xc0001ee600}, {0xc00003bd30, 0x4}, {0x13f1520, 0xc000014018}, 0xc0000a4050?, {{}, {{0x0, {0xc00003bd28, ...}}}, ...})
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/types/token.go:104 +0x318
github.com/oasisprotocol/oasis-sdk/client-sdk/go/modules/accounts.(*Transfer).PrettyPrint(0x13f1520?, {0x13f9040?, 0xc0001ee600?}, {0xc00003bd30?, 0xc0001b5878?}, {0x13f1520?, 0xc000014018?})
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/modules/accounts/types.go:18 +0xab
github.com/oasisprotocol/oasis-sdk/client-sdk/go/types.(*PrettyTransaction).PrettyPrint(0xc000194640, {0x13f9040, 0xc0001ee600}, {0x10717ae, 0x2}, {0x13f1520, 0xc000014018})
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/types/transaction.go:523 +0x29e
github.com/oasisprotocol/oasis-sdk/client-sdk/go/types.(*Transaction).PrettyPrint(0x13f1520?, {0x13f9040, 0xc0001ee600}, {0x10717ae, 0x2}, {0x13f1520, 0xc000014018})
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/types/transaction.go:265 +0x13a
github.com/oasisprotocol/oasis-sdk/client-sdk/go/types.(*UnverifiedTransaction).PrettyPrint(0xc0001ee360, {0x13f9040, 0xc0001ee600}, {0x0, 0x0}, {0x13f1520, 0xc000014018})
        /home/oa/go/pkg/mod/github.com/oasisprotocol/oasis-sdk/client-sdk/go@v0.4.0/types/transaction.go:135 +0xbc5
github.com/oasisprotocol/cli/cmd/common.PrintTransaction(0xc00012d7c0, {0xf74340?, 0xc0001ee360})
        /home/oa/cli/cmd/common/transaction.go:296 +0x39f
github.com/oasisprotocol/cli/cmd.glob..func41(0x1a9f120?, {0xc00009b7c0, 0x1, 0x4?})
        /home/oa/cli/cmd/tx.go:85 +0xbb
github.com/spf13/cobra.(*Command).execute(0x1a9f120, {0xc00009b740, 0x4, 0x4})
        /home/oa/go/pkg/mod/github.com/spf13/cobra@v1.7.0/command.go:944 +0x847
github.com/spf13/cobra.(*Command).ExecuteC(0x1a9e880)
        /home/oa/go/pkg/mod/github.com/spf13/cobra@v1.7.0/command.go:1068 +0x3bd
github.com/spf13/cobra.(*Command).Execute(...)
        /home/oa/go/pkg/mod/github.com/spf13/cobra@v1.7.0/command.go:992
github.com/oasisprotocol/cli/cmd.Execute(...)
        /home/oa/cli/cmd/root.go:36
main.main()
        /home/oa/cli/main.go:6 +0x25

[kostko]

@matevz, it should be fixed now.

[matevz]

Tested, works