wrote a section about CouchDB (in Chaper 4), added a subsection describing TouchDB in general
removed the red comments outlining some of the chapters/sections
some amendments on 4.2 CouchDB
small amendment to 4.4.1 TouchDB/about
added a section about the document design/schema migration (4.3.1)
started describing the Couch entity relations, in detail the space-error code
Merge commit '7e6b574143499ddca27c9dd485bcc45d8f362e86'