partial fix for newline terminators

Because the largest delimiter is two bytes, aleph waits for a
second byte before terminating the frame.  If the last line in
a sequence of metrics ends in a newline it is ignored.

input       |expected|actual
------------|--------|------
in1\n       |in1     |
in1\nin2\n  |in1, in2|in1
in1\nin2\r\n|in1, in2|in1, in2
Merge pull request #7 from bfritz/newline-handling

metrics must end with CRLF