Handle extension wallet TX results

[lachlanglen]

Extension wallets are much easier than web wallets, from a UX perspective (much smoother flow) and also for developers (no redirect handling, ability to "await" TXs).

Right now, if a user on my app is using Meteor wallet extension (5-star rating with 2000 users), I have to poll the smart contract being called to be able to verify that the transaction succeeded, and can't handle a failed tx at all.

Ideally, I should be able to wait for the result of the transaction, in the case of an extension wallet, and handle a success or error within the flow of the component logic.