DevDocs corrections part 1

Started reviewing the developer docs, finding lots of things to correct. I'll do more later, but please review this batch first so I know what, if anything, needs to be fixed moving forward - I'm not entirely sure on the markdownish format used.
We settled on using "satoshi" as the term of generic value.  See the [style guide](https://github.com/bitcoin/bitcoin.org/wiki/Documentation-Style-Guide#default-unit-of-value-satoshis) and the [issue where we discussed this](https://github.com/saivann/bitcoin.org/issues/20)