Check if running environment supports colored output

[sebastianheuer]

Currently UnixoidEnvironment::supportsColoredOuput() always returns true without really verifying that the current environment does actually support colors. This should be determined on runtime, maybe using tput colors.

[dnaber-de]

Nice labeling to guide possible new contributors 👍 I'll start to put some effort on this the next days…

[sebastianbergmann]

You may want to have a look at https://github.com/sebastianbergmann/environment/blob/master/src/Console.php#L29

[dnaber-de]

From SebastianBergman\Environment\Console::hasColorSupport():

    if (DIRECTORY_SEPARATOR == '\\') {
        return false !== getenv('ANSICON') || 'ON' === getenv('ConEmuANSI') || 'xterm' === getenv('TERM');
    }

Is that for Windows OS? If so, it could be a possible implementation for WindowsEnvironment::supportsColoredOutput() which currently returns always false.