[#60948610] added ability to define code tutorials with tie in to Git pr...

New mechanism for adding tutorials. 

tuts.rb defines the tutorial
tutorial [filename],[title],[group],[git-project-url]
do
  gitlabel [Stepname], [Title]
end

filename: name of overview file found in tutorial folder
title: title of tutorial to be displayed in menu
group: not used right now but will be to group tutorials
git-project-url: base url for project - used to display step comparisons

gitlabel:
Stepname: label used in git project, content of step mush be filename.Stepname.txt, also used in diff compare
title: used in menu

Ex:
tutorial 'emberjs', 'Using EmberJS in RhoMobile Apps','Javascript MVC','https://github.com/rhomobile/rhotut-emberjs' do
  gitlabel 'step-0',                 'This is Step 0'
  gitlabel 'step-1',                 'This is Step 1'
  gitlabel 'step-2',                 'This is Step 2'

end