Make this free of any syntax additions

[dead-claudia]

It makes this much easier to get started with, and the more I look at and play with the syntactic version, the more it just feels too Perl-ish.

Forewarning, though: the builtin implementations of the various methods isn't trivial. This is probably the hardest part of the whole proposal, thanks to the very complex nature of performant low-level async primitives.

Existing remaining work:

• Create polyfill for Object.then/Symbol.then
• Create polyfill for Object.asyncThen/Symbol.asyncThen
• Create polyfill for Object.combine/Symbol.combine
• Create polyfill for Object.asyncCombine/Symbol.asyncCombine
• Create polyfill for Object.merge/Symbol.merge
• Create polyfill for Object.chain/Symbol.chain
• Create polyfill for Object.asyncChain/Symbol.asyncChain
• Create polyfill for Object.box
• Update main proposal text to use functions instead of syntax
• Update main proposal text to link to the polyfill