Added missing memoryTracking to test cases 560 and 583. If this triggers
leak detection on these, it only means that previously it was going unnoticed.
CURLM_CALL_MULTI_PERFORM stopped being a valid return code from
curl_multi_perform back in 7.20.0. All the libcurl tests are ajusted to
this and no longer check for this return code. Makes them simpler.
All C and H files now (should) feature the proper project curl source
code header, which includes basic info, a copyright statement and some
basic disclaimers.
