Add PGP key for Luke Dashjr (BD02942421F4889F)
DevDocs: Don't recommend BitcoinTalk
Refer to BitcoinTalk by name
Bugfix: "merkle root" and "merkle tree" are common nouns, so generally lowercase
DevDocs: Block Chain: The important part is ordering, not timestamping
DevDocs: Block Chain: Overview: Many corrections
DevDocs: Block Chain: Proof of Work: Many corrections
DevDocs: Block Chain: Block Height and Forking: Many corrections
DevDocs: Block Chain: Transaction Data: Many corrections
Merge remote-tracking branch 'remotes/luke-jr/master' into master