Use HTTPS for Twitter.

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>
Fix SSL error handling.

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>
Make the SSL_ca_file option configurable.

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>
Ship 5.1.6.

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