Upgrade for first gis project
Cakefile: add extra/ docs processing
docs: add extras/ docs; update all source docco comments
models: move gis.html & data to sketches/ (github can't run it)
DataSet:
  - asc and image datasets now have two function each,
    one to turn an image/string into a dataset, the other to use
    import image/xhr and then call the image/string function.
    imageDataSet: turn image into dataset, importImageDataSet using import
    ascDataSet: turn asc str into dataset, importAscDataSet using import
  - toDrawing: turn dataset into image and call patches.installDrawing
  - imageDataSet: rgb default, alpha usable thus 24 & 32 bit datasets
Animator: refactor
Model:
  - add toggle for animator
  - setup called at end of ctor again; remove setup from setupAndGo
  - reset: stops anim and restarts if was running on entry