More moderation tools and stats enpoints

[jayserdny]

Changes made:

• Reserve a post so another moderator cannot moderate it (unless the moderation is expired)
• Reduce the number of queries by passing objects through middlewares using locals
• Add new members to the moderation team (can be added as a moderator or supervisor)
• Reset moderation data (supervisors only)
• Demote moderators and/or supervisors. (Only master supervisor can demote supervisors and not vice-versa)
• Improve API docs by adding parameters default values and specify if they are optional
• Stats endpoints: pending, approved, moderated, not-approved, reserved posts. (They all can be queried by a specific user as well)
• Update package.json to decrement the version of the API back to 1.0.0 and change the author
• Remove coded relate to JWT and users
• Clean up unused code and unused libraries