Merge pull request phaserjs#1026 from lucbloom/spritesheet-report-key

Report key when failing

Author: photonstorm

src/animation/AnimationParser.js

@@ -59,7 +59,7 @@ Phaser.AnimationParser = {
         //  Zero or smaller than frame sizes?
         if (width === 0 || height === 0 || width < frameWidth || height < frameHeight || total === 0)
         {
-            console.warn("Phaser.AnimationParser.spriteSheet: width/height zero or width/height < given frameWidth/frameHeight");
+            console.warn("Phaser.AnimationParser.spriteSheet: '" + key + "'s width/height zero or width/height < given frameWidth/frameHeight");
             return null;
         }