feat(Porthole): report when event listeners throw errors for debugging purposes (Porthole.error)
feat(Porthole): report when event listeners throw errors for debugging purposes (Porthole.error)

Currently, when a listern function throws an error the exception is *silently swallowed*.
Debugging information was added in order to improve developer experience.

Porthole.error(e) was also tweaked. Added an additional type check for `window.console.error`.

ternarylabs/porthole,ternarylabs/porthole,ternarylabs/porthole