Added the scripts bitcoin-testnets*

[GraoMelo]

hi,
I want to congratulate all of you on the nmap project.
I've always found it fabulous and I've used it a lot over time.
Often, because of this, I want to contribute to the project.

I studied the commit of Mr. Patrick 8a175d1
with the description:

[NSE] Added the scripts bitcoin-info, bitcoin-getaddr and a supporting
Bitcoin library. The script bitcoin-info retrieves information about the
remote server, while the bitcoin-getaddr script retrieves a list of
discovered remote Bitcoin nodes. [Patrik]

I saw that the following files were modified:

nselib/bitcoin.lua
scripts/bitcoin-getaddr.nse
scripts/bitcoin-info.nse
scripts/script.db
Also the changelog.

My contact is to add a feature that can contribute.
Bitcoin has several test networks that can help researchers who are auditing nodes that in turn may not have value if
they are running a testnet.
Recently, some projects want to use the bitcoin testnetV3 network as if it were the mainnet production network.
I want to contribute a new module that checks if the node is listening on a specific testnet port and in turn will
report the version that the bitcoin-cli is running (the name is not exactly that).
Bitcoin has Testnet, Regtest, Signet, all of which run the same RPC protocol that has already been implemented in
Patrick's PR "[NSE] Added the scripts bitcoin-info"

My contact is to find out what the best way to do this is?
Do I create the issue and then the pull request on GitHub? (I'm aware that it's just a mirror there)
Do I make the contribution directly to the svn:
svn DOT nmap DOT org/nmap??

What is the best way to standardize the contribution.
...
scripts/bitcoin-testnet.nse
,,,