Doxygen_1.8.9 is added which should be used to generate doxygen files,Rdesigneur folder is creater under "user" folder and corrected index.rst file is updated, deleted "html" folder,Rdesigneur markdown file with correct date,"snippet " and "tutorial"folder is created with relevant files to generate html files

update-repository is moved from scripts to moose folder which pull the code from submodule recursive