note development dependencies
node iter over deps & provide name
revert name repr
add dfs generator in util module
add util mod to autodoc
improve docs on utils & df code
clear up stupid comments
arithmetic methods on Expr
expr -> arith
rm i/r variants, not needed
util.bcast pre compute broadcasted shape
cover extra cases
more flexible bcast use
implement reduction shape
begin testing shape propagation
Add docs, tests for shape
move vb specific class to vb
reworking the object model
work out model
simplify ir model