move the documentation to markdown

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@home.org.au> (github: SvenDowideit)

Please do not commit to this branch - I will bring any changes made to the move-to-markdown branch into this one as needed. 

This is an all in one commit to simplify working out what has changed and does not include the generated .md files which will be commited in a subsequent PR