Make dataset plot methods available as functions.

[juseg]

Make ~dataset~ ~plot~ methods Dataset.hyoga.plot.method(self, ...) available as functions hyoga.plot.function(ds, ...).

• [ ] ~Add dataset plot functions in hyoga.plot.datasets.~
• [ ] ~Add dataset calc functions in hyoga.calc.interp etc.~

[juseg]

I am planning to do it for plot methods only. My idea is that v0.2 will ship with a variety of unbound plot functions for vectors (Natural Earth, paleoglaciers, shapefiles) not using datasets. Instead of mixing object-oriented and unbound code:

import hyoga.plot
ds.hyoga.plot.ice_margin()
hyoga.plot.rivers()

Some users might prefer a fully non-oo equivalent:

import hyoga.plot
hyoga.plot.ice_margin(ds)
hyoga.plot.rivers()

On the other hand something like hyoga.calc.interp(ds) would require a new module hyoga.calc (or many top-level functions). I don't see anything that would fit in hyoga.calc but not in ds.hyoga. Forgetting about hyoga.calc.

[juseg]

I am backtracking on this one (see 6a61dcb). Thanks to GeoPandas (#24) shapefiles can be plotted as objects. This beautifully removes the need for any non-object-oriented plot interface (that hyoga.plot would have been). Hyoga will stick object-oriented plotting.