Lazy loading for Arrow.jl

[jfb-h]

In the wake of tecosaur/DataToolkitCommon.jl#16 you activated lazy loading for ArchGDAL so that .gpkg data can be loaded even when ArchGDAL was not explicitly imported by the user before. The same seems to be the issue for Arrow files where currently you get an ERROR: TransformerError: Data set ... could not be loaded in any form. when you don't load either the Arrow or DataFrames package first.

[tecosaur]

I think it should suggest now that you need to load the Arrow or DataFrames.

Regarding ArchGDAL, IIRC you still need to load it first? At least in the unit tests it is.

[jfb-h]

I'll check again, maybe I got something mixed up. When and how to load and add packages felt a little bit confusing sometimes, if I remember correctly.

[tecosaur]

The loading code has been largely rewritten at this point, and so I'll mark this as resolved unless I hear otherwise.