Dependency Updates

[ErisDS]

Updates the majority of our dependencies which were out of date. All of these updates are minor bumps with no obvious breaking or affecting changes.

Excluded are:

• bookshelf & knex, see Bookshelf & Knex upgrade #6103
• bluebird, see Update Bluebird dependency #6361
• glob, as other dependencies require that we use v5 still
• lodash, as the latest version is a significant breaking change, and it probably makes sense to wait for more of our dependencies to update before we do.
• nodemailer, as we are stuck on the 0.7 branch, see Update nodemailer from 0.7 to 1.0 #4125
• showdown-ghost, see Making ghost compatible with showdown main #5598