Multiple changes in one PR (sorry)

[jhoneill]

There is some documentation in Changes_James.txt and more detail in docs/examples .docx.
Summary. I've added extra parameters to node, edge and record to allow more to be defined, and changed the parameters in edge so you can create objects with to, from, label, style and direction properties and pipe them into edge.
To go with record I created a cells function.
To make it easier to set-up and pass attributes I've made commands for creating edge and node attribute sets (with parameter completers).
Finally to go with the work I was doing where I needed the output to go to std-out I made a mod so a an empty string passed as the destination path does that - but not passing anything selects a random file name. That allows SVG files to be sent to a (Jupyter) Notebook with .NET interactive :)

Sorry to drop multiple changes on you, feel free to use or discard as you see fit.
J

[KevinMarquette]

Awesome work, lots of good ideas. It will take me a bit to review these changes but I appreciate the effort you put into it. I may publish it as a 2.0 prerelease version.