Provide accurate documentation for brain_observatory_cache.get_eye_tracking

[chaseking]

Overview:

I was involved in generating eye tracking files and packaging them into a format that can be used in the BrainObservatoryCache. I noticed the method to access these data did not have proper documentation; this commit gives the method proper documentation to ensure the user knows what the method returns.

Type of Fix:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing
  functionality to not work as expected)
• Documentation Change

Solution:

Implements correct documentation for the method

Changes:

Documentation on the get_eye_tracking method in brain_observatory cache is amended to describe the returned data array. Changes are entirely in method documentation comments and thus unit tests are not needed.

Validation:

N/A

Checklist

• My code follows
  Allen Institute Contribution Guidelines
• My code is unit tested and does not decrease test coverage
• I have performed a self review of my own code
• My code is well-documented, and the docstrings conform to
  Numpy Standards
• I have updated the documentation of the repository where
  appropriate
• The header on my commit includes the issue number
• My Pull Request has the latest AllenSDK release candidate branch
  rc/x.y.z as its merge target
• My code passes all AllenSDK tests

Notes:

[CLAassistant]

All committers have signed the CLA.