Draft: Add metadata file for NotesApp.

Required

• The app complies with the inclusion criteria
• The original app author has been notified (and does not oppose the inclusion)
• All related fdroiddata and RFP issues have been referenced in this merge request
• Builds with fdroid build

Strongly Recommended

• The upstream app source code repo contains the app metadata (summary/description/images/changelog/etc) in a Fastlane or Triple-T folder structure
• Releases are tagged

Suggested

• External repos are added as git submodules instead of srclibs
• Enable Reproducible Builds
• Multiple apks for native code

Extra: I haven't tested if the app builds with fdroid build, I will mark the PR ready to merge once I'm sure it does build.

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