Sort chinese apps by their pinyin transliteration

Close #61

ktx/src/main/java/de/mm20/launcher2/ktx/String.kt

@@ -1,7 +1,25 @@
 package de.mm20.launcher2.ktx
 
+import com.github.promeg.pinyinhelper.Pinyin
 import java.net.URLDecoder
+import java.util.*
 
 fun String.decodeUrl(charset: String): String? {
     return URLDecoder.decode(this, charset)
+}
+
+/**
+ * Normalize a string to lowercase ASCII
+ * TODO: Only supports Chinese/Pinyin at the moment
+ */
+fun String.normalize(): String {
+    return this.romanize().lowercase(Locale.getDefault())
+}
+
+/**
+ * Romanize a string, transliterate non-latin characters into latin
+ * TODO: Only supports Chinese/Pinyin at the moment
+ */
+fun String.romanize(): String {
+    return Pinyin.toPinyin(this, "")
 }