Add skin fixer

src/main/kotlin/moe/nea/firmament/features/fixes/Fixes.kt

@@ -0,0 +1,16 @@
+package moe.nea.firmament.features.fixes
+
+import moe.nea.firmament.features.FirmamentFeature
+import moe.nea.firmament.gui.config.ManagedConfig
+
+object Fixes : FirmamentFeature {
+    override val identifier: String
+        get() = "fixes"
+
+    object TConfig : ManagedConfig(identifier) {
+        val fixUnsignedPlayerSkins by toggle("player-skins") { true }
+    }
+
+    override fun onLoad() {
+    }
+}