Tutorial doc fixes

[FloatingFront]

Started the tutorial doc fixes.

[FloatingFront]

Just as a suggestion, copied tutorial material structure from

https://github.com/absinthe-graphql/absinthe/tree/master/guides/tutorial

to

https://github.com/absinthe-graphql/absinthe_tutorial

with the following change suggestions:

• added /src subdirectory to the /tutorial directory
• put the *.md files into this /src subdirectory

(the *.md files will be the "source file" for generating the *.html files so nothing is changing on the help document creating front...)

created two scripts (either one will do - you choose which one you like better - note the resulting name difference of the generated *.html files) ,

• convert-md-to-html.sh generates the *.html files into the parent directory
• make-html-from-md.sh generates the *.md.html files into the parent directory

(again, the difference is in the naming of the resulting html files : *.html vs. *.md.html )

The resulting html files are added to the git repo, but should ideally be generated on fly from the md files, but that is more difficult to achieve and would need more changes - other projects are probably already have that sorted in some fashion.

The tool used by the scripts for generating the html from md files is http://pandoc.org/MANUAL.html