Add new permissions to plugin.yml and permission kits. Set scoreboards to enabled per player by default.
Update WG versions to not break compatibility reported in issue #81
Add faction announcements to send to all players and show to players when they login if they were not online when it was first sent as requested in issue #82.
Make faction open command async as everything there is thread safe. Resolves issues of players timing out servers in. Closes #84
Refactor scoreboard usage

In preparation for team colors, we need to unify scoreboard usage into a
single scoreboard per player.

Rather than creating a new scoreboard for each desired sidebar
objective, we provide an interface FSidebarProvider that allows
implementation-agnostic retrieval of the title and lines of the desired
sidebar, along with appropriate methods in the new implementation of
FScoreboard.

The new FScoreboard implementation manages the currently-visible
sidebar, with methods to set default (non-timed, with update interval)
and temporary (timed, no update interval) sidebars.

Temporary sidebars are replaced with the default sidebar upon
expiration.
Add ally/neutral/enemy team colors to FScoreboard