Allow purified fns to pass args after scope
Make tap work again by passing tapped fn
Rewrite to actually work with passing

* Works with primitive types, now.
* No more laziness.  Impossible to figure out fns that need to be added to the wrapper during the lazy stage, because have no idea what data types will be passed along chain.
Simplify example
Remove accidentally left over line of code
Pull out dupe context setting code into fn
Rename context to ctx
Make sure to update meths after invoking fn

* They could change after a call if we are in pass mode and the invoked fn returns something of a different "type" from the previous invocation target.
Add chafe.adhoc()
Add example of adhoc() to test
Make chafe API functions into methods.

* Purify only partly purifies.  It makes the fn rely only on its args, but it doesn't omit side effects on those args.
Better demo in test.js
Remove comments from test now they are in the readme
Add readme
Make readme include example of this()
Add this()
Add gitignore
Add package.json
Add tests
Start w chained obj as return value AND this