Symfony 5, phpspec 6 and PHP 7.2

Upgraded to:

• Symfony 5
• phpspec 6.1
• PHP 7.2

phpspec 5

Upgraded phpspec to v5.0@rc, meaning:

• phpspec v4 support was dropped
• PHP 7.0 support was dropped
• Symfony 2.7, 3.0, 3.1, 3.2 and 3.3 was dropped
• added usage of void return type
• added usage of constant visibility

Normalized float to double

Normalization from float to double, thanks to @ItsKelsBoys

Added PHP 7.2 support

Thanks to @roukmoute for adding PHP 7.2 support

Fixed float arguments

Marked float as being a non object type, thanks to @Arn0d

phpspec 4 stable

Using phpspec 4.0 stable, thanks to @Arn0d

Memio 2.0

Using Memio 2.0, thanks to @Arn0d

phpspec 4

Upgraded phpspec to v4.0@rc, meaning:

• phpspec v2 and v3 support was dropped

Scalar Type Hints

Upgraded Memio to v2.0@alpha, meaning:

• PHP 5 support was dropped
• scalar arguments now get type hinted
• maximum method argument line length changed from 120 to 80
• opening curly brace changed to be on the same line as the method
  closing parenthesis, when arguments are on many lines
• properties changed to not have empty lines between them,
  except if they have PHPdoc

Re-enabled Constructor Generator

Constructor generator wasn't registered as a generator in phpspec 3,
du to a missing DI tag.