Value function improvements: removes the prefix when creating the snapshot, thanks Mal Curtis

As apply uses the snapshot, this means that declarations in the DOM need to omit the value function prefix

TODO: update() support, and ensure de-camel-casing only happens with letter prefixes
Value functions: check that prefix requires initial cap before lowercasing, also change RegExp for more standard JS
scope.$.set (and thus update) now support value function prefixes where the property name being set must not include the prefix
README: document value function prefix change