Help updates

restructured help topics
changed link syntax

changed cross-reference links from markdown to github flavored markdown
updated link syntax 2

updated link syntax (again)
Revert "updated link syntax 2"

This reverts commit b0f1d7f793e7db07a0d783d1d750578cf9f49895.
fixed typos
fixed broken links

corrected references to cross references and relative paths
split 1 topic into 2

separated creating custom templates and hosting apps online
fixed ordered list

replaced bullets with numbers
Clean-up and footers
Fixed typos
Merge branch 'help_updates'