Change tested PHPUnit version

Summary: - a bug was fixed in json_encode in PHP5
 - phpunit added a defined('HHVM_VERSION') test and now tested the incorrect behavior when on HHVM
 - we fixed the bug in HHVM
 - we start failing the test becuase of the defined.

New version of phpunit tests HHVM_VERSION

fixes facebook/hhvm#2913

Reviewed By: @JoelMarcey

Differential Revision: D1377807
Add Composer JSON test to clownlist

Summary: Both HHVM and PHP5 fixed a bug - test is now a bad test.

https://github.com/composer/composer/issues/3049

Reviewed By: @JoelMarcey

Differential Revision: D1377837
Update NEWS for Mos Def

Reviewed By: @ottoni

Differential Revision: D1377939
Disable broken FunctionInfo optimization to avoid unboxing function returns

Summary: It doesn't work because of __call.

Reviewed By: @swtaarrs

Differential Revision: D1373642
add stats for requests timeout and memout in psp

Summary: D949107 added counters in hhvm for # of requests killed due to timeout or memory
exceeds. But that only covered the code path for the main part of the request
and not PSP. This diff hooks up the counters for psp timeouts and memouts.

Reviewed By: bmaurer

Differential Revision: D1365105