Changed the asciidoc script to use the asciidoctor implementation
Aligned the macro definitions in the Comp Ref and Dev guides
Replaced asciidoc macros for guibutton and guilabel with a custom backend
Changed some ++ literal blocks to ## attribute blocks
Replaced the +> file macro with >>>
Added the bleathem asciidoctor fork as a git submodule
Simplified the asciidoctor invocation script
Merge remote-tracking branch 'origin/master'