No easy way to find out book version
Submitted by Maciej Katafiasz
Link to original bug (#134336)
Description
There should be easy, unified way to check version of book, this is kinda essential when we talk about API :). Probably will need enhancement to book format, and in this case IMO it should be obligatory (or at least heavily recommended) to supply that information in book. Right now chasing various FOO_BAR_MAJOR definitions in books is driving me crazy, not to mention fun of having more than one version installed.