Bump certifi from 2018.1.18 to 2018.8.24 (#21)
Bump certifi from 2018.1.18 to 2018.8.24 (#21)

Bumps [certifi](http://certifi.io/) from 2018.1.18 to 2018.8.24.

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
JamieMagee/reddit2kindle,JamieMagee/reddit2kindle