Only use ansi colors for var_dump() if supported
\TYPO3\FLOW3\var_dump() currently uses ANSI codes to colorize variables on the CLI.
On Windows that's not supported by default and instead all special characters are outputted.
I don't know how to detect ansi support from PHP, so I would suggest to disable this on Windows for now.
The change is trivial:
$ansiColors = $plaintext;
$ansiColors = $plaintext && DIRECTORY_SEPARATOR === '/';