* sample sisu markup "Free as in Freedom": book index markers included
* identify markup helpers updated

* html segments, name more accurately
* rough description of how book index markup works
* clean out book index from these outputs
* book markup sample, free as in freedom, start doing book index, only letter "A" done so far
* texpdf, url matching, special characters
* # Please enter the commit message for your changes.

* middle layer document representation changed, (accounting for substantial patch)
* texpdf multiple document sizes as specified in config
* numerous small fixes
[should on the whole be easier to maintain]