Enable points mode category axis

Enable "points" mode in Axis.Category and add test that verifies range values in different range type.
Add update range after setting range type.

Close #919.
While I agree for this specific case, there's one thing I just throught up.  rangeType does not fail if a certain code path is used, meaning that this PR is still technically independent, albeit you'll be using a path that might be a tiny bit awkward to use (The path I'm thinking is to essentially not set the range until rangeType is set.).  While this is not ideal, it does show that this PR can be 100% independent I think.