Version 0 of HelpViewer - based on Tkhtml2.0

JOB 16-08-22

Modified the source of the helpviewer package - based on Tkhtml2. Please see code below.

Some notes:

• Tkhtml3 html widget command has a different interface compared to Thktml2 and does not show command options, which makes it hard to do any development, so for the moment Tkhtml2.0 - although not actively developed any more - is still an option to choose.
• There are various dependencies in order to run the helpviewer, which are non included here.

• helpviewer.tcl

• helpviewer_demo.tcl

• main.tcl

• Makefile.tcl