Migrate ROOT I/O to uproot
This PR closes #1200 (closed) by re-implementing the ROOT-format input/output routines for Table
and subclasses to use uproot
. This is a much lighter library that is available on all platforms and doesn't require a working ROOT installation.
This should be API compatible, since everything is under-the-hood, but there are likely small differences that may trip up users who use ROOT I/O heavily - I don't actually know of anyone doing that.