gaiacli: Make recovery allow new keys

[ValarDragon]

Closes #1474

• Updated all relevant documentation in docs
• Updated all code comments where relevant
• Wrote tests
• Updated CHANGELOG.md - n/a, bug fix that was introduced in this PR
• Updated Gaia/Examples
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)
• Added appropriate labels to PR (ex. wip, ready-for-review, docs)

[cwgoes]

I think we want to use CreateFundraiserKey here; it just doesn't really fit with the current LCD API.

cc @liamsi

[ValarDragon]

Would you prefer reverting CreateFundraiserKey, and making seperate methods "Create Key" and "Create FreshKey"?

[codecov]

Codecov Report

Merging #1477 into develop will not change coverage.
The diff coverage is 0%.

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  Files          118      118           
  Lines         6563     6563           
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  Hits          4141     4141           
  Misses        2151     2151           
  Partials       271      271

[cwgoes]

Ah, sorry, I mean that we want to use CreateMnemonic in the usual case and CreateFundraiserKey only for fundraiser keys.

[ValarDragon]

Create Mnemonic wouldn't work here, that derives the mnemonic. We need to go from mnemonic to privkey. I don't understand the rationale behind having a seperate CreateFundraiserKey method as opposed to a generalized CreateKey method, since the functionality is exactly the same, and any downstream application can just run CreateKey. (i.e. LCD endpoints could just call CreateKey with the exact same input)

[cwgoes]

Create Mnemonic wouldn't work here, that derives the mnemonic. We need to go from mnemonic to privkey. I don't understand the rationale behind having a seperate CreateFundraiserKey method as opposed to a generalized CreateKey method, since the functionality is exactly the same, and any downstream application can just run CreateKey. (i.e. LCD endpoints could just call CreateKey with the exact same input)

Exactly; I don't think we need to expose two separate methods for creating a mnemonic and then deriving a key from the mnemonic, ref #1442. For deriving keys from previously created mnemonics, we can use the Derive method.

[ValarDragon]

Decided to keep CreateFundraiserkey, and temporarily create a new CreateKey method just to resolve the #1474 bug. The real solution will happen as a result of #1480

[cwgoes]

Tested ACK, thanks!