OutputCache: fixed storing of catched output

[marc-mabe]

No description provided.

[ClemensSahs]

please add a ob_end_clean().

because we must close the ob level correctly

[marc-mabe]

@ClemensSahs:

http://php.net/manual/function.ob-get-flush.php
ob_get_flush() flushes the output buffer, return it as a string and turns off output buffering.
Note: This function is similar to ob_end_flush(), except that this function returns the buffer as a string.

[ClemensSahs]

ok I got it confused with ob_get_content()