Fix usage of obsolete Chinese character in example

DanielYang59 on GitHub: The capical of China should always be written as "北京"
instead of "北亰".

Closes #108

Author: DanielYang59

unidecode/__init__.py

@@ -5,7 +5,7 @@
 Example usage:
 
 >>> from unidecode import unidecode
->>> unidecode("\u5317\u4EB0")
+>>> unidecode("\u5317\u4EAC")
 "Bei Jing "
 
 The transliteration uses a straightforward map, and doesn't have alternatives