Add support for StakeAddress and BaseAddress output

[kevink1103]

This PR includes:

• Deprecate Wallet.Addresses() and replace it with Wallet.EnterpriseAddresses()
• Deprecate Wallet.Keys() and replace it with Wallet.PrvKeys()
• New Wallet.BaseAddresses()
• StakeAddress support for Address and Wallet
• Add PoolCost in poolRegistration struct

closes #45
closes #20

[kevink1103]

Looks like I just made a duplicate feature of #41 ... but my PR includes tests for the feature.
Choice is up to you, @echovl .

[safanaj]

Regarding the StakeAddress management this and #41 are pretty equivalent, I can split #41 to just add easy-to-use bech32 end/dec, and get this merged.
Pls @echovl give us a feedback

[kevink1103]

@safanaj it was too late when I finished implementing StakeAddress management on my own and later found out you've done similar work in #41 PR...
I would appreciate it if you could split your PR to only include bech32 utilities and have it merged first because I think my PR takes care of more address-wise changes (baseAddress, some function changes in Wallet, tests...). Then, I'll update my code with some of your new works.

[kevink1103]

@echovl Could you allow few more people to review PRs and have write access to the repo so that they can merge PRs as well? Hope this repo to be a bit more responsive and prosper :)

[safanaj]

@safanaj it was too late when I finished implementing StakeAddress management on my own and later found out you've done similar work in #41 PR... I would appreciate it if you could split your PR to only include bech32 utilities and have it merged first because I think my PR takes care of more address-wise changes (baseAddress, some function changes in Wallet, tests...). Then, I'll update my code with some of your new works.

Agree, yes I will. Only I saw that on my PR in address.go there are 2 typo fixes in the NewAddressFromBytes constructor, regarding the error message for Ptr address type if those make sense to you too add them.

@echovl if you are still short with time probably as suggested by @kevink1103 you could allow us to review and merge.

[kevink1103]

@safanaj Thank you! I've just taken care of the typos you've mentioned. Let's wait for @echovl 's review!

[kevink1103]

As this PR will adopt changes from #41 , I will make this PR as draft for now so that #41 gets merged first. cc. @safanaj

[echovl]

Hi guys, sorry for the late reply, this looks good to me. Do we really need the bech32 PR merged first?

[kevink1103]

@echovl Hi, welcome back!
and whichever is fine for me. As soon as #41 PR gets merged, I can take advantage of prefixes defined there. So we can still merge this one first. I'll put this PR ready for review.

[kevink1103]

Just to follow up on this PR.
Since this PR has not been paid enough attention and reviewed, I have forked this repo and added more features on top of this PR.
https://github.com/ffdd/cardano-go

For those who are interested in this PR, use the forked one!