Implement "Chimaps in a few lines of code"

[wkearn]

This series of articles on the blog presents how to construct chimaps with TopoToolbox v2. I think turning these blog posts into Jupyter notebooks would be a useful way to organize some of our next steps with pytopotoolbox as well as giving some more structure to the documentation.

I will go through these posts more closely to identify more concrete tasks and open the appropriate issues. I think we can do many of the steps already, namely creating FlowObjects and StreamObjects. There are a few preprocessing steps that I don't think we have Python solutions to yet, and we can also take this opportunity to improve the visualization interface of pytopotoolbox. The chi transform itself or at least the integration along the stream network can probably be implemented in libtopotoolbox.

Update:

I more or less copy-and-pasted the blog posts into a Jupyter Notebook. I will push that up as a draft PR so we can look at it, but these are the things that I think we need to implement to be able to run the entire example:

• GridObject.inpaintnans
• Improve visualization of StreamObject #111
• GridObject.griddedcontour
• StreamObject.modify
• FlowObject.drainagebasins
• Extract watersheds within certain boundaries
• StreamObject.chiplot
• StreamObject.chitransform #75