[Looks OK?] Attempting to make the library work for DASH as well as BTC

[dbolser]

Hello,

This is less of a 'pull request' and more of a 'request for feedback' on the way I've (crudely?) begun to implement DASH support for the library. I think there may be a cleaner, more modular way to do this, so any feedback on what I've done here would be appreciated. Of course I plan to add mainnet-DASH and testnet-DASH as well as LTC, BCH, ETC., but before I do that, I'd like to get some feedback on just how hacky this approach is... Also, would you consider maintaining a branch that contains these changes?

Many thanks,
Dan.

[dgpv]

If you only need to change chain params, you do not need to patch the library. You can subclass MainParams and CoreMainParams and monkey-patch bitcoin.params and bitcoin.core.coreparams (or if you are going to change the source, maybe add special function like SelectAlternativeParams(main_params, core_params), that you call instead of SelectParams, like this: https://github.com/Simplexum/python-bitcointx/blob/master/examples/litecoin-alt-p2sh-prefix.py)