[BUG] Error handling

[alvinkl]

Describe the bug
If something error during rendering either on server or client, I think it's best that Maleo able to cope with the error, as simple as exposing a function that's going to get called by the time the error appears, or a customisable error page on the server

To Reproduce
Steps to reproduce the behavior:

1. Throw error on render (ran on both server and client)
2. See nothing appears on the screen

Expected behavior
At least a user customisable error page

Desktop (please complete the following information):

• OS: Mac OSX High Sierra
• Browser chrome
• Version 75.0.3770.90