fix a bug about ImportError

jieba/analyse/__init__.py

@@ -1,6 +1,9 @@
 import jieba
 import os
+try:
 	from analyzer import ChineseAnalyzer
+except ImportError:
+	pass
 
 _curpath=os.path.normpath( os.path.join( os.getcwd(), os.path.dirname(__file__) )  )
 f_name = os.path.join(_curpath,"idf.txt")