R4R: CLI subcommands reorganization

[alessio]

• Subcommands reorganisation. A comprehensive list of renamings follow:
  - tendermint validator-set -> query tendermint-validator-set
  - tendermint block -> query block
  - account -> query account
  - stake delegation -> query delegation
  - stake delegations -> query delegations
  - stake parameters -> query parameters
  - stake pool -> query pool
  - stake redelegation -> query redelegation
  - stake redelegations -> query redelegations
  - stake signing-info -> query signing-info
  - stake unbonding-delegation -> query unbonding-delegation
  - stake unbonding-delegations -> query unbonding-delegations
  - stake validator -> query validator
  - stake validators -> query validators
  - stake create-validator -> tx create-validator
  - stake edit-validator -> tx edit-validator
  - stake delegate -> tx delegate
  - stake redelegate -> tx redelegate
  - stake unbond -> tx unbond
  - stake unjail -> tx jail
  - gov deposit -> tx deposit
  - gov query-proposal -> query proposal
  - gov query-proposals -> query proposals
  - gov query-vote -> query vote
  - gov query-votes -> query votes
  - gov submit-proposal -> tx submit-proposal
  - gov vote -> tx vote
  - broadcast -> tx broadcast
  - send -> tx send
  - sign -> tx sign
• Remove unused (and misspelled) SignTxRequstHandler.

Closes: #1184

• Linked to github-issue with discussion and accepted design OR link to spec that describes this work.
• Wrote tests
• Updated relevant documentation (docs/)
• Added entries in PENDING.md with issue #
• rereviewed Files changed in the github PR explorer

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For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@91cac96). Click here to learn what that means.
The diff coverage is n/a.

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[cwgoes]

Minor comments. Can we add q as a shortcut for query, e.g. gaiacli q redelegation (or is that too much)?

[cwgoes]

utACK, thanks @alessio