Add macro support for player account database

[cwisniew]

Is your feature request related to a problem? Please describe.
Add add player, remove player, and reset password macros as part of #2673

[Phergus]

#2966 Added macro functions

Non Trusted
player.getName() => Returns current player name
player.getInfo() => Returns info current player (name, role, is connected)

Trusted
player.getInfo(name) => Returns info specified player (name, role, is connected)
player.getPlayers() => Returns info about all known players (name, role, is connected)
player.getConnectedPlayers() => Returns info about connected players (name, role)

When not using the player database (which requires server started with checkbox ticked) the known players will only be the currently connected players.

[Phergus]

Testing.

From GM client, all functions worked as expected.

On player client, getInfo() & getName() functions thrown an exception whether run trusted or un-trusted:

java.util.concurrent.ExecutionException: java.lang.NullPointerException: Cannot invoke "net.rptools.maptool.model.player.PlayerInfo.name()" because "playerInfo" is null
Error trace : Get Info@campaign

java.lang.NullPointerException: Cannot invoke "net.rptools.maptool.model.player.PlayerInfo.name()" because the return value of "java.util.concurrent.CompletableFuture.get()" is null error executing expression player.getName().
Error trace : Get Name@campaign

Also on player client, both getPlayers() and getConnectedPlayers() return the info for only the GM player but uses the Default Username as set in preferences and not the GM name as entered on the Start Server dialog.

[{
  "name": "Default Username",
  "role": "GM",
  "connected": true
}]

[Phergus]

Passing player.getInfo("nobody") a name that isn't in database produces an exception:

java.util.concurrent.ExecutionException: java.lang.NullPointerException: 
   Cannot invoke "net.rptools.maptool.model.player.PlayerInfo.name()" because "playerInfo" is null
Error trace : Get Info Error@campaign

[Phergus]

Wiki pages added for player.getName, .getInfo(), .getPlayers, .getConnected.
https://wiki.rptools.info/index.php/Category:Player_Database_Function

[Phergus]

Tested. Issues reported above have been corrected.