sprite collection editor v2.1

I've been updating the tutorials for the past few days. Tutorial 1: Making a basic pink engine game, Tutorial 2: More Map Design and Tutorial 3: Sprite Collections and NPCs have now all been updated to reflect the changes to the engine made since their initial publishing. However, when working on an updated tutorial for the Sprite Collection Editor, I noticed a couple of bugs that popped up, as well as some improvements that could be made. Hence, I'm publishing the brand new Sprite Collection Editor v2.1. 

In the new version, translating an image now automatically results in the 'move_to', 'base_offset_x_start', 'base_offset_y_start', 'base_offset_x_end' and 'base_offset_y_end' properties being set for every animation. This should save a lot of time if you want to translate a lot of images to the pink engine. 

The new version also raises an error when trying to export a sprite collection without first setting a sprite collection name. In prior versions, exporting without a name would result in a messed up output folder structure. 

Fixed an error where the editor would occasionally return errors if, after saving a sprite collection, you tried to make further changes or export, as well as an error that would occasionally pop up when adding a new property after translating an image. 

The updated tutorial should follow tomorrow.