Admin Dashboard

[kersploosh]

[Opening a new issue based on a comment in #160]

Consider having an admin dashboard which lists information about the instance and its users. Include the ability to sort and filter based on various traits.

List all local users, with filters for:
registration email
age of account
time since last activity (login, vote, post, or comment)
IP address of most recent login
number of reports submitted by user
number of reports targeting the user

List all local communities, with filters for:
number of subscribers
number of posts
most recently active moderator
time since that moderator was last active
a flag if a community has no moderator, or no moderator with activity in the past X days

List all received reports targeting local users or communities, with filters for:
targeted user
instance of targeted user
community containing the targeted post/comment
reporting user
instance of reporting user

List all sign-up applications that are waiting to be approved, with filters for:
Username
IP address
Registration email
Application text

[Pdzly]

I would add to the local users and sign ups filter:

User Agent