Memcached unknown command causes a lost line in command pipeline

From Michal:

"memcached server consumes one more line of input than it has to when unknown command occurs.

input:
"bogus\r\ndelete a\r\n"
expected output:
ERROR
NOT_FOUND
actual output:
ERROR

input:
"bogus\r\ndelete a\r\ndelete a\r\n"
expected output:
ERROR
NOT_FOUND
NOT_FOUND
actual output:
ERROR
NOT_FOUND

input: "bogus \r\ndelete a\r\ndelete a\r" (space after bogus) behaves as expected

check MemcachedDecoder.scala, line 45
readLine consumes next line even when it was already done by readElement"