Epoch name appears to clobber other parts of file

[nicain]

1) Bug

Steps to Reproduce

try:

    for name in ['epochs','fizzbuzz' , 'stimulus']:

        filename = os.path.join(gettempdir(), "test_%s.nwb" % name)

        nwbfile_out = NWBFile(
            source='Data source',
            session_description='test foraging2',
            identifier='behavior_session_uuid',
            session_start_time=datetime.datetime.now(),
            file_create_date=datetime.datetime.now(),
            epochs = Epochs(source='foo', name=name)#epoch_table
        )

        with NWBHDF5IO(filename, mode='w') as io:
            io.write(nwbfile_out)

        nwbfile_in = NWBHDF5IO(filename, mode='r').read()
        print nwbfile_in.epochs.name

except Exception as e:
    
    traceback.print_exc(limit=2)

output:

epochs
fizzbuzz
Traceback (most recent call last):
  File "/home/nicholasc/projects/pynwb/issues/epochs/sandbox.py", line 30, in <module>
    nwbfile_in = NWBHDF5IO(filename, mode='r').read()
  File "/home/nicholasc/projects/pynwb/src/pynwb/form/utils.py", line 343, in func_call
    return func(self, **parsed['args'])
ValueError: builder 'templates' does not have a data_type

Environment

Please describe your environment according to the following bullet points.

• Python Executable: Conda
• **Python Version:**Python 3.6
• Operating System: Linux
• Pynwb Version: git tag latest, branch dev

Problem/Use Case

Briefly describe the needed feature as well as the reasoning behind it

It appears that the name a user gives an Epoch object when constructing the file is a keyword, and can clobber the other componenets of an NWBFile on write.

Checklist

• Have you ensured the feature or change was not already reported ?
• Have you included a brief and descriptive title?
• Have you included a clear description of the problem you are trying to solve?
• Have you included a minimal code snippet that reproduces the issue you are encountering?

[ajtritt]

#633 will address this. Right now, ObjectMapper doesn't see that the name is specified to be "epochs". When building the /epochs GroupBuilder, it only works off of the neurodata_type_def specification (i.e. from nwb.epochs.yaml) and doesn't see that NWBFile has set it's name to be "epochs".