Version 0.15.2

Welp, my prediction of how long it'd take for the next release was way off, but at least it's out now. This particular patch was brought to you by the discord, featuring several requested features and fixing several reported bugs. 

• Sprite collection objects can now be passed a variable name as their path, and will switch between collections as the variable changes value.
• The pink engine now supports conditional layers. Unlike conditional objects,  which check their condition every frame, conditional layers only check their condition when entering a map. This allows you to have vast conditional areas in your maps without slowing down the engine.
• The `get_follower` function has been added to the pink module itself, allowing you to call it even when no pink engine map is currently visible. 
• Fixed a bug where, when triggering a touch event, the player character would not complete their final frame of movement. 
• Fixed a bug where interacting with the edge of the map could cause a fatal error.
• Fixed a bug where the game could crash if certain incompatible controllers were even so much as plugged into your computer.
• Added a number of tests maps to demonstrate these features, as well as a number of other previously possible functionalities that had been poorly documented.
• Swapped out all the invisible objects with icons in the test maps, to provide visual clarity to people checking out the maps for the first time (since Tiled doesn't outline object outlines by default). 

The new test rooms are E19 through E23

• E19 demonstrates the new conditional layer feature, with a set of possible conditional super layers that only renders depending on a ren'py variable.
• E20 demonstrates how to get a specific follower to perform an action during an event, no matter where that follower is in the follower order.
• E21 demonstrates how to attach an activation event to a follower. 
• E22 demonstrates how to use a variable sprite collection, as well as demonstrating how to ensure that an NPC doesn't show up on the map if they're already your follower. 
• E23 demonstrates how to use conditionals to create (the illusion of) tiles that the player can both walk under and over. Both vertical and horizontal bridges are demonstrated in this room.

That's it for this update. Unless I discover more bugs, or get more requests for neat minor features, the next update will be 16.0. I have finally learned my lesson, and will make no predictions about how long it will take.