Add function for creating overlays of text

[GoogleCodeExporter]

Generate text overlays automatically using the Google Charts API.

https://chart.googleapis.com/chart?chst=d_text_outline&chld=000000|36|h|ffffff|b
|Sample+first+line.|and+a+second+line!

http://chart.googleapis.com/chart?chst=d_simple_text_icon_above&chld=Single+line
+of+text|20|000000|medical|12|F88|FF0000

Original issue reported on code.google.com by tylerick...@gmail.com on 23 Feb 2012 at 9:05