0.05 Minor perlcritic adjustments. Also hoping a rebuild will fix
     CPANTS license complaints.

0.04 Added transparent background support (b="transparent")

0.03 Fixed divide-by-zero, thanks for the report, Todd!
     Added a few more tests

0.02 Fixed off by one error
     Extended to support different chart types using 't' param (t='b' by default)

0.01 Initial release