PHP-1033: Organize third-party code and license information.
Merged pull request #646
PHP-1038: Do not allocate zval to set command cursor batchSize
Merge pull request #641
PHP-1040: MongoCommandCursor::key() should not return _id field

This also updates aggregateCursor() tests to log query/getmore requests. New tests were added for getmores due to limit/batchSize relations, as well as an error test case for invalid batchSize options.
Add missing "proto" in MongoCommandCursor methods