remove all non-success response examples
Merge branch 'develop' into markdown
all XML and JSON blocks pass validation
Merge branch 'develop' into markdown
Merge branch 'develop' into markdown

Conflicts:
	source/API_Reference/Customer_Subuser_API/apps.html
render markdown in info and warning blocks
remove html(!)
add markdown
remove "markdown=1" cruft
fix validator to check .md and .html, remove mis-tagged json block
remove unnecessary whitespace and fix {% endresppnse %} indentation
more whitespace cleanup
revert all problem .md files to .html
fix {% endparameters %} indentation
more formatting tweaks
Merge pull request #473 from sendgrid/markdown

Convert most HTML to Markdown