Implement API endpoint for image alignment

[jonchang]

Is your feature request related to a problem? Please describe.
In order for front end to access the ability of the OCR backend to perform image alignment, an API endpoint needs to be written to expose this functionality

Describe the solution you'd like
A new API endpoint that will accept as arguments a "reference" image and a "target" image, such that the target image will be aligned to the reference for use in segmentation OCR downstream

Describe alternatives you've considered
n/a

Additional context
Continuation of #226