Rename misleading use of raw_input so it's not automatically converted to input by 2to3.

IPython/core/tests/test_inputsplitter.py

@@ -28,7 +28,7 b' from IPython.core import inputsplitter as isp'
 # Note: at the bottom, there's a slightly more complete version of this that
 # can be useful during development of code here.
 
-def mini_interactive_loop(raw_input):
+def mini_interactive_loop(input_func):
     """Minimal example of the logic of an interactive interpreter loop.
 
     This serves as an example, and it is used by the test system with a fake
@@ -43,7 +43,7 b' def mini_interactive_loop(raw_input):'
     while isp.push_accepts_more():
         indent = ' '*isp.indent_spaces
         prompt = '>>> ' + indent
-        line = indent + raw_input(prompt)
+        line = indent + input_func(prompt)
         isp.push(line)
 
     # Here we just return input so we can use it in a test suite, but a real