add libbitcoin, obelisk and sx

[mikegogulski]

(Someone might want to alphabetize this list, so I did a wee bit of that by adding the projects in almost-alpha order.)

[saivann]

I can't really judge if suggested additions are all relevant, but in general, I think it's only good to list more libraries. Agreed on re-ordering the list in alpha order.

[mikegogulski]

libbitcoin other is an alternate implementation of the Bitcoin core protocol, much as bitcoinj is. sx is a command-line tool for working with transactions with a libbitcoin/obelisk back-end, and obelisk itself is a libbitcoin-based block/transaction server.

[luke-jr]

These sound relevant to me. Is there a reason not to include more of the DarkWallet stuff?

[saivann]

@luke-jr Not that I know, this could also be submitted in a pull req.

[harding]

These inclusions sound fine to me. However, if the only criteria for inclusion on this list is a free software license (or, hat tip to @mikegogulski, a public domain grant), maybe it would be better to keep this list on the Bitcoin Wiki.

[mikegogulski]

@harding: Thanks for the h/t :) I kinda disagree with keeping this list on the Wiki, however, since the standards for updating it are much lower than the main bitcoin.org website. The Wiki already suffers from fraud/phish attacks on a regular basis.

[saivann]

@harding Is it because you fear this list will grow too much? Perhaps we can see if this becomes a problem in the future, but so far this seemed to be working OK IMO. Maybe we can require libraries to be minimally known (attract at least a small number of developers and users) before being listed.

[harding]

@saivann Hmm. I guess I just like giving people the tools they need to do stuff on their own. Anyway, I suggest no more debate about this today---this PR LGTM.

[saivann]

In the absence of critical feedback, this pull request will be merged on May 26th