[+BUGFIX] Security Randomizer produces a Warning on Windows
If openssl is not available, the 3rd party script we're using to
generate random bytes executes
$fp = @fopen('/dev/urandom', 'rb')
Despite of the Error Control Operator a warning is produced that
leads to an exception in Development mode.
This is fixed by checking the OS here and only execute those lines
on unix based systems.
Note: As this is a 3rd party script we need to contact the author
regarding this change!