Utils: improve performance by opening files only once (thanks Guibou!)

utils/rules.py

@@ -155,14 +155,16 @@ for filename in songfiles:
        else :
           print "Warning: language is not defined for song : " + filename
 
-       songfile.seek(0)
-       songfile.write(data)
-       songfile.truncate()
-       
-for i, line in enumerate(fileinput.input(songfiles, inplace = 1)):
+       lines = data.split('\n')
+       for index, line in enumerate(lines):
           #remove trailing spaces and punctuation
           line = line.rstrip().rstrip(',.;').rstrip()
           #remove multi-spaces within lines
           line = re.sub("(?P<last_char>\S)\s{2,}","\g<last_char> ", line)
-#write correct line
-   sys.stdout.write(line+'\n')
+          lines[index] = line
+
+       data = "\n".join(lines)
+       songfile.seek(0)
+       songfile.write(data)
+       songfile.truncate()
+