Started IPython notebook.

Need to reformat plotly package first!!
Separated out Exporter(PlotlyRenderer).run(fig) from fig_to_plotly(fig).

Changed code in plotly_renderer to include a definition for a
fig_to_plotly function which opens a web browser with plot data taken
from matplotlib and sent to plotly.

Also, the file in the examples directory was updated to take this change
into account.
Merge branch 'reformat-ren' into ipynb
Functional IPython notebook in notebooks directory.

IPython notebook runs, but plotly plot is not embedded in notebook yet.
Added option for iplot or plot in plotly_renderer for IPython notebooks.

You can now toggle the fig_to_plotly function by adding the 'notebook'
keyword (i.e., notebook=True) so that the plot will be dropped directly
into your ipython notebook.
Just added Apple's .DS_Store to .gitignore file.