* Updated the bundled Zandronum ACC with Zan 3.1 changes

* Add Zandronum 3.1 functions and constants to its ACS configuration

* Updated the Zandronum ACC (again), as it was missing GAMESTATE definitions

When choosing a difficulty or engine in the test toolbar button the engine will not be launched immediately. This can be reverted in the preferences. Resolves #626

UDBScript: fixed a problem where a version warning was shown then the script version was not equal to the UDBScript version (instead of only showing the warning when the script version was higher)

UDBScript: the methods of the Pen class now return the instance of the Pen class to allow method chaining. Resolves #662

IPK3 and IPK7 with an IWADINFO lump with a single IWAD definition are now recognized as the main resource file (used for the -iwad parameter when testing). Fixes #653

Hexen Game Configuration: fixed a problem where the default arguments of the Death Wyvern had special names, even though they actually don't do anything in game. Also renamed the thing from "Dragon Lich" to the correct "Death Wyvern". Fixes #660

UDBScript: fixed a problem where using QueryOption resulted in an exception being thrown. Fixes #661

ZScript: user variables of parent actors were not displayed in the custom tab of the thing editing dialog. Fixes #649

Fixed a problem where DeHackEd lumps failed to parse when their header wasn't at the beginning of the file. Fixes #647

Drag Geometry Mode: floor and ceiling panning are now correctly preserved when dragging geometry. Fixes 648

Added map scripting capabilities to UDB (#656). Documentation at https://biwa.github.io/udbscript-docs/

ZScript parser: fixed a bug where trying to parse the undocumented alternative array declaration syntax failed. Fixes #645

Fixed an issue where thing positions were modified even when the new position was the same as the old one. Fixes #644

ZScript parser: fixed a bug where included files where parsed when the #include directive was encountered, and not after the rest of the file was parsed. Fixes #641

Visual Mode: fixed a bug where textures on 3D floors were not scaled correctly when using the upper/lower texture 3D floor flags. Fixes #640

Script editor: added support for the //$Skip editor in scripts. Adding this line will not add the next script to the drop down list of available scripts for the ACS actions in the thing and linedef editor dialogs. Resolves #636

Image Exporter: added option to chose between taking sector colors into account or not when exporting. Resolves #635

Image Exporter: fixed a bug where texture scales were not taken into account when exporting. Fixes #634

ZScript: fixed a problem where whitespace between a state label and the colon resulted in a parsing error. Fixes #631

(G)ZDoom game configuration: added several missing UDMF fields for linedefs and sectors, so that they show up in the custom tab. Fixes #628

UDMF reader/writer: fixed a bug where unknown top level fields and blocks were not preserved. Fixes #627

Visplane Explorer: fixed a bug where changing the settings after re-entering the mode would result in a crash. Fixes #624

Fixed a problem where floating point numbers for actor radius and height were not interpreted correctly. Fixes #623

Added an option to run commands before and after resources are reloaded, and before testing a map. This option can be accessed from the map options dialog.