Should we use Reflect.metaData?

[emolr]

Looking at https://github.com/kenchris/lit-element/blob/master/src/lit-element-decorators.ts, Kenneth is using Reflect metadata to determine the type if no options are set.

Only issue is that if no options or type defined in TS, then the value type returns as an object, which causes the content of an attribute to be interpreted wrongly in some cases.