Improve error handling

[daanboer]

The current method of handling errors is by throwing and catching exceptions. However it is easy to forget, and cumbersome, to try-catch everywhere necessary. Moreover, Typescript can't help because there is no way to signal that a function might throw. Error handling can be much improved by using a library such as true-myth, which calls for explicit handling of errors. This will squash any surprise bugs at runtime due to uncaught exceptions, and it will improve the developer experience as Typescript will signal the developer that a function might error and force them to handle it correctly.