Remove the inappropriate use of the Photo Galleries category.

src/apps.json

@@ -2593,8 +2593,7 @@
 		},
 		"FlexSlider": {
 			"cats": [
-				"5",
-				"7"
+				"5"
 			],
 			"icon": "FlexSlider.png",
 			"implies": "jQuery",
@@ -4360,7 +4359,6 @@
 		},
 		"Lightbox": {
 			"cats": [
-				"7",
 				"12"
 			],
 			"html": "<link [^>]*href=\"[^\"]+lightbox(?:\\.min)?\\.css",
@@ -5478,8 +5476,7 @@
 		},
 		"OWL Carousel": {
 			"cats": [
-				"5",
-				"7"
+				"5"
 			],
 			"html": "<link [^>]*href=\"[^\"]+owl.carousel(?:\\.min)?\\.css",
 			"icon": "OWL Carousel.png",
@@ -7311,7 +7308,6 @@
 		},
 		"Slimbox": {
 			"cats": [
-				"7",
 				"12"
 			],
 			"html": "<link [^>]*href=\"[^/]*slimbox(?:-rtl)?\\.css",
@@ -7322,7 +7318,6 @@
 		},
 		"Slimbox 2": {
 			"cats": [
-				"7",
 				"12"
 			],
 			"html": "<link [^>]*href=\"[^/]*slimbox2(?:-rtl)?\\.css",
@@ -7685,7 +7680,6 @@
 		},
 		"Supersized": {
 			"cats": [
-				"7",
 				"25"
 			],
 			"icon": "Supersized.png",
@@ -9929,7 +9923,6 @@
 		},
 		"prettyPhoto": {
 			"cats": [
-				"7",
 				"12"
 			],
 			"env": "pp_(?:alreadyInitialized|descriptions|images|titles)",