clean up, all markdown files will be placed under docs/user/markdown, images...

clean up, all markdown files will be placed under docs/user/markdown, images under /docs/images one can use markdown2rst.py to convert Rdesigner,MooseGui and Kkit docs which places the file under docs/user/GUI and docs/user/Rdesigneur and further one can use makefile to convert to rst to html which will be placed under _build folder in respective folders