[hpsdr] Introducing a "Path Illustrator" feature

[Joe Martin]

Thanks to all who have already provided feedback on the initial version of the Path Illustrator feature.  I have fixed several of the problems reported and have posted a new version (v1.2.3 18Dec2015) on the download site.  

Also I have posted a “Path Illustrator change log" text file on the download page to keep track of changes as they occur.  

73, Joe K5SO