add defineProperties and createFromNull helpers to begin.js
moved createFromNull to begin.js, where it is needed
got rid of a load of hasOwnProperty checks
inherit default options from null so we lose the hasOwnProperty check
added test to see if an indexOf check is redundant... remove later if so!
typo
fixed bug with unregistering dependants multiple times
appease the linter
appease the linter
ractive.observe() only returns an object with a cancel method - update is private
eliminated .call() when dealing with custom events