handle deprecation of variable initialization methods

[jacobsn]

I get the following warnings

WARNING:tensorflow:From evaluate.py:55 in .: initialize_all_variables (from tensorflow.python.ops.variables) is deprecated and will be removed after 2017-03-02.
Instructions for updating:
Use tf.global_variables_initializer instead.
WARNING:tensorflow:From evaluate.py:56 in .: initialize_local_variables (from tensorflow.python.ops.variables) is deprecated and will be removed after 2017-03-02.
Instructions for updating:
Use tf.local_variables_initializer instead.

I tried to fix this at some point but couldn't figure out the correct replacement.