I Entry points:
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A IntentSearchFeatures:
Called by CommCare to identify ear during followup

 1 EarCaptureActivity
    Camera to capture ear image or choose last taken photo.

 2 SIFTActivity
    Receives images from EarCaptureActivity
    Computes EarFeature of image and retrieves features with PatientLoaderCommCare
    For every Patient in PatientHashMap calculates the Distance with the EarFeature
    Sends TopMatchesList to next activity

 3 SelectFollowupActivity
    Receives and displays TopMatchesList for selection of patient.
    Returns selected match or register instruction to CommCare

B IntentTransferFeatures:
Called by CommCare to store features during registration

 1 EarCaptureActivity
    Camera to capture ear image or choose last taken photo.

 2 SIFTActivity
    Computes features of image and return them to CommCare

II Utils:
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FileCache
Handles temporary files for images and features.

ImageUtils
Handles camera image location and name

OpenCvUtils
Resizes matrix to speed up features