Add ServerListPingEvent player list API. Adds BUKKIT-5121, BUKKIT-2465
[Bleeding] Fix logic for calculating slot in Creative mode. Fixes BUKKIT-4715

Previously, hotbar slots for player inventory would return 9 - 18 while in
Creative mode, rather than 0 - 9. This commit fixes the logic used for
calculating the returned slot based on the raw slot.
Add methods to get and set knockback strength in Arrow. Adds BUKKIT-5103
Add setCritical and isCritical methods to Arrow.java. Adds BUKKIT-5113
[Bleeding] Add ProjectileSource interface. Addresses BUKKIT-1038, BUKKIT-1156
[Bleeding] Add setCharged and getCharged to WitherSkull. Adds BUKKIT-3060
Added SpawnReasons for nether portals and dispensers. Fixes BUKKIT-3148

Previously any entities spawned through dispensers (monster eggs) or
by nether portals were given the incorrect SpawnReason of SPAWNER_EGG.
This made it impossible to distinguish what exactly happened in regards
to the creature being spawned.

With the additional two SpawnReasons, plugins can identify sources of
creature spawning more easily and accuratly.
Add banning API and resolve associated command issues. Adds BUKKIT-3535.
Fixes BUKKIT-5371 and BUKKIT-4285

Prior to this commit, ban reasons were not supported by banning commands.
Additionally, the player(s) affected by the ban-ip command would not have
been removed from the server via a kick.

The Bukkit API lacked support for modifying various attributes associated
with bans, such as the reason and expiration date. This caused various plugins
to use external or other means to store a ban reason, making the built-in
banning system on the server partially useless.

Now the ban commands will accept reasons for the bans as well as kick the
player from the server once banned. That means that if an IP is banned
that all players using that IP will be removed from the server.

The API provided now supports editing the ban reason, creation date,
expiration date and source. The ban list has also been created to
provide this information more easily. Editing the data requires an
implementing plugin to manually save the information with the provided
method in BanEntry or BanList once changes have been made.

The addition of this API has deprecated the use of OfflinePlayer#setBanned()
as it has been replaced by BanList#addBan().
[Bleeding] Blacklist certain plugin names
[Bleeding] Blacklist ":" in command names.
[Bleeding] Simplify command handling.

Instead of duplicating code to handle two pools of commands
we can instead just add the fallback commands after all
plugin commands are loaded and achieve the same effect. We
also now always register the direct address of a command
to ensure it is always possible to access it.

In addition, aliases can be determined by whether or not
the command label of the command matches the command address,
thereby rendering the aliases HashSet redundant.
[Bleeding] Improve alias system.

Adds a large expansion of the aliases system. Aliases can now take arguments,
reorder their arguments, and only pass certain arguments to certain commands.
New syntax added to the aliases are $1 for optional arguments, $$1 for
required arguments, $1- for optionally using all the arguments from the
specified position onward, and $$1- to do the same thing but require at least
the specified position exist. These exist for numbers 1 through 9. You are
able to pass arguments to one command of a multiple command argument and not
others. You can also use the argument as a prefix and/or suffix. A raw $ can
be represented in the arguments by using \$.

Examples:

aliases:
# Usage: /testobjective score_deaths 1 5
testobjective:
- "testfor @p[$$1=$$3,$$1_min=$$2]"

# Usage: /ban Amaranthus Because reasons
ban:
- ban $$1 $2-
- say Banned $$1

# Usage: /icanhasbukkit
icanhasbukkit:
- version

# Usage: /icanhasplugin HomeBukkit
icanhasplugin:
- version $$1

One change from the previous aliases system is that commands are no longer
passed all arguments implicitly. You must explicitly pass the arguments
you want to pass to the command.
Pulling all pending Bukkit-JavaDoc changes
[Bleeding] Fix formatting of optional arguments.
[Bleeding] Also blacklist ":" in plugin command aliases.
[Bleeding] Fix getCommand for conflicting plugin commands.
[Bleeding] Implement escape sequence for aliases.
[Bleeding] Support any number of arguments in aliases
Clean up alias handling.

There is no need to print a stacktrace when an alias fails, we do not do
this for normal commands. We also now give error messages when attempting
to register an alias instead of having them just silently not function.
Remove extra events from alias execution.

When executing an alias we already call an event for the alias itself. The
extra events are not needed for logging purposes as the alias itself is
logged and the events cause issues for plugins trying to do spam checking
on their own.