Feature request: don't lose user profiles when version changes

[JackMostow]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is: Lose user profiles when change version.

Describe the solution you'd like
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Don't change versionName in build.gradle. Instead, use a different variable DisplayVersion.
See RoboTutorLLC/RTFace_Login#51

Describe alternatives you've considered
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Could store profiles in files and load them, but it would take more work.

Approach to be followed (optional)
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See RoboTutorLLC/RTFace_Login#51.

Additional context
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