Fix specs for MethodProphecy

[tkotosz]

Currently when running phpscpec for the MethodProphecy class then I get the following:

$ vendor/bin/phpspec r spec/Prophecy/Prophecy/MethodProphecySpec.php 
                                                                                 0
0 specs
0 examples 
0ms

It seems this happens because a new class is defined before the MethodProphecySpec class which seemingly not allowed.

I have moved that other class to the bottom of the file then the tests started to run but a few of them was failing so I fixed those in this PR.

after the fixes:

[tkotosz]

php 5 build fixed now, please let me now if there is a better way to fix it :)

[stof]

Should rather be dropped entirely, as this class does not actually have void typehinted methods, and skipping this case in the specs on PHP 5.

[tkotosz]

will see how to create a double manually instead of asking in it as a method argument (like now in its_constructor_records_default_callback_promise_for_return_type_hinted_methods) otherwise the php5 build would fail since the ClassWithVoidTypeHintedMethods class would be missing

[tkotosz]

ok, managed to work around it

[tkotosz]

@stof fixed the PR based on your feedback. Could you please have a look again?

[tkotosz]

squashed commits to prep the PR for merge