More control of bar styles

[moscarillo]

This is a nice library. Thank you!!

Ran into a design request which we couldn't fulfill and perhaps others may see benefit in these styles.

1. Ability to control height of bars
2. Ability to control number of bars

perhaps the ability to pass in a barStyle and remove/replace barColors

[lannex]

There seems to be a constant request for custom styling. I will consider it positively.