master: markdown/bin/slides update to support windows and unix
master: markdown/bin/preview: update to support local img preview
master: markdown/bin: update build-all.sh and add build-slides.sh
master: markdown/bin/slides: update slide-mac.sh, etc.
master: markdown/bin/: update markdown.bat and slides.bat
Merge branch 'master' of https://github.com/MichaelHu/myscripts