Version 1.3.0

• The minimum required PHP version has been increased to 5.6
• Updated the test suite to work with PHPUnit 6
• Updated the travis build to test for PHP 7.1
• Updated to latest coding standards
• Added SecureRandom::getRandom() which returns a random float between 0 and
  1 with more uniform distribution and always less than 1.
• Added SecureRandom::getUuid() which returns a random version 4 UUID.
• Added Generator\ByteNumberGenerator that wraps non NumberGenerator
  generators for generating random numbers
• Improved the bundled autoloader slightly