Bar Chart with hover text example.

- Add https://plot.ly/~etpinard/344/500/500/ to docs
- Make PR https://github.com/plotly/documentation/pull/6 obsolete
- (??) geom_histogram and gg-alpha have been published successfully
can we change to "Bar Chart with Hover Text" just to be consistent with the rest of the examples on the page? you *should* be able to run something like `$ python run.py meta bar-with-hover-text` so that you don't have to re-run all of the examples (right @theengineear ?)