Exclude retweets.
Ship 5.1.3

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>
Blacklist makebot.

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>
Ship 5.1.4

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>