Generate extended public keys from an extended key

[cosmin-harangus]

Given an extended public/private key generate the corresponding extended public keys in "legacy", "p2sh-segwit" or "bech32" address types (if supported) These can then be used by hd-addr to check the generated addresses for funds as mentioned in issue #28 .

[dan-da]

This patch doesn't seem to work.

Firstly, the get-extended param is not read from the command-line. maybe you forgot to commit changes in Util.php?

Even after I added that, I get an error that $key is undefined on line 54 of hd-wallet-derive.php. After fixing that, I got another error.

If you fix the PR so that I can test it out, I will evaluate further. thanks.

[cosmin-harangus]

You're right, I missed a few things there... Too eager to push I guess. I will fix it in the new few days and update the PR. These changes were taken from another project where I needed to run this package as a JSON server instead of through the CLI.

[dan-da]

ok, yeah I'll take a look once you update...

[cosmin-harangus]

I've updated the PR with the fixes and tested the solution. Please confirm and let me know if there are other other changes that I should do. I tried to used the same naming conventions in order to match the current usage style.