add validate cmd to tx and query subcmds

[colin-axner]

Closes: #310

Description

Adds validation to the usage of the tx and query commands.

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• Wrote unit and integration tests
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[fedekunze]

utACK

[alexanderbez]

utACK 🌮

[alexanderbez]

Not sure why setup-dependencies is stuck. I seem to have lost permissions in CircleCI. Maybe @alessio can give it another run?