* Appear to have fixed displacement tracking
* Strain plotting or strain calculation is incorrect
* Flipped image that is plotted so axis directions of matrix indices line up with axis direction of image
* Changed quiver plotting to use "dot" as units so now the position and displacement is in units of pixels.
* Started putting displacement and strain plots on the same figure so they can be compared side-by-side
* Decreased subset spacing to get more tracking points
* Changed displacement calculation to account for the template matching function returning the upper-left corner of the matching window rather than the center.
* Added variables to restrict search size for matching pattern.
* Rotated images back to normal that were rotated for some reason
* Created an ImageData class to hold displacements and strains in each image.
Used OpenCV to find matching template and draw arrows of displacement.
Made a plot using each template matching method.
SQDIFF and SQDIFF_NORMED appear to be best.
* Add new class SpecimenDimensions to hold dimensional information.
* Add stress variable to FrameData class.
* rename calc_stress function to read_file
* Add data filepath as input to read_file function
* read_file function now calculates stress from cross-sectional area
of specimen and load from each frame.
* read_file function now returns dictionary (indexed by frame number)
of FrameData objects that have load, displacement, and stress data.
Also returns SpecimenDimensions object that holds width, thickness,
gauge length, and overall length.
Created main.py with a function to read in the provided text file.
Gets specimen dimensions, frame number, load, and displacement data into
dictionary of FrameData classes.
