[processing] small fix to R provider

Author: ghtmtt

python/plugins/processing/algs/r/RAlgorithm.py

@@ -116,7 +116,7 @@ def parseDescription(self, lines):
         self.passFileNames = False
         self.verboseCommands = []
         ender = 0
-        line = lines.next().strip('\n').strip('\r')
+        line = next(lines).strip('\n').strip('\r')
         while ender < 10:
             if line.startswith('##'):
                 try: