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.
Although it's not currently mentioned in the style guide (I'll update it), we use Microsoft Technical Style for headings and subheads, in which the first letter of each word is capitalized unless it's a proper noun that starts lowercased (e.g. iPhone).  The same style is also used for illustration captions and abbreviation expansions.