Addressing text layer alignment issues

An attempt to improve alignment in documents with 'justified' text see
#3713

Good results with following

* https://dl.dropboxusercontent.com/u/20922503/justified/A_Tale_of_Two_Cities_T.3.pdf
* https://dl.dropboxusercontent.com/u/20922503/justified/copywrite.4.pdf
* https://dl.dropboxusercontent.com/u/20922503/justified/History1.pdf

But very poor with
* https://github.com/sirdsoriano/doc/blob/master/pdf.js/9788490040737_4.pdf