fixed erroneous discreteBarChart example in the docs; fixed url in README.rst; chmoded screenshots from 0755 to 0644
fixed discreteBarChart.png to really match the doc example
created a seperate dir for the doc example images ("doc_images")
turned the multiBarChart doc example into something that makes some sense
Merge pull request #34 from tnt/master

Changes to the doc examples I complained about