Use icon theme so we can have more than one icon size per icon

resources/multimc/index.theme

@@ -0,0 +1,30 @@
+[Icon Theme]
+Name=multimc
+Comment=MultiMC Default Icons
+Inherits=default
+Directories=scalable/apps,8x8,16x16,22x22,24x24,32x32,48x48
+
+[scalable/apps]
+Size=48
+Type=scalable
+MinSize=1
+MaxSize=512
+Context=Applications
+
+[8x8]
+Size=8
+
+[16x16]
+Size=16
+
+[22x22]
+Size=22
+
+[24x24]
+Size=24
+
+[32x32]
+Size=32
+
+[48x48]
+Size=48