Straight `\n` characters are *not* acceptable in GELF messages
Straight `\n` characters are *not* acceptable in GELF messages

Undo the straight `\n` changes from the GELF decoder test.

Keep the rewrite hack around while broken clients get fixed, but remove it
from the documentation.

jedisct1/flowgger,jedisct1/zok,jedisct1/zok,salpalvv/flowgger,salpalvv/flowgger,jedisct1/flowgger