Added a readme explaining how to generate html from markdown docs w/o node

Author: jesse99

doc/README

@@ -0,0 +1,13 @@
+The markdown docs are only generated by make when node is installed (use
+`make doc`). If you don't have node installed you can generate them yourself. 
+Unfortunately there's no real standard for markdown and all the tools work 
+differently. pandoc is one that seems to work well.
+
+To generate an html version of a doc do something like:
+pandoc --from=markdown --to=html --number-sections -o build/doc/rust.html doc/rust.md && git web--browse build/doc/rust.html
+
+The syntax for pandoc flavored markdown can be found at:
+http://johnmacfarlane.net/pandoc/README.html#pandocs-markdown
+
+A nice quick reference (for non-pandoc markdown) is at:
+http://kramdown.rubyforge.org/quickref.html