round edges of progress

[DawnImpulse]

Hello,
Loved the library and all your extra efforts you added to the original forked one.

There is one feature request from my side. Can there be an option for rounded progress bar corners? Where you can specify in XML the do to which you wish to round the edges.

It would be a great addition, let me know what you think :)

[DawnImpulse]

and one more thing, it would be awesome to have an option to specify margin between two progress bars.

Let me know if you like me to work on these things. I will submit a PR afterward. Waiting for a reply :)