Add in-app release notes

[evan10s]

This is definitely not necessary by any means but it would pair nicely with our update prompts.

[kberzinch]

Is this also through play store or do we need backend support for this?

[evan10s]

Not through Play Store, but I was thinking it'd be a few bullets about the latest version packaged into the build, though I haven't given implementation much thought

[kberzinch]

Oh you mean after the new version is installed, i thought you meant as part of the update prompt or something like that