Remove ansi colours escape codes in output

This removes ANSI escape sequences from standard output and error.

Reasons I've hit for stdout/stderr being coloured:

* Test runner may colour output
* "pretty" printed logs when in development mode
* Some middleware may also do it (e.g.: [io.aviso.exception](https://github.com/AvisoNovate/pretty#ioavisoexception) )

So far I've avoided disabling colours in each of these cases, as they are useful when using the REPL in the terminal.