docs: add info about customizing the density of an AVD from command line; and a few editorial things like fix the TOCs Change-Id: I4e301fe005d8fb4d04550b7db5afe2b63fe66802
docs: add info about customizing the density of an AVD from command line; and a few editorial things like fix the TOCs Change-Id: I4e301fe005d8fb4d04550b7db5afe2b63fe66802