Create an Android build

[tophyr]

Pull Request Type

• GitHub Workflow changes
• Documentation or Wiki changes
• Build and Dependency changes
• Runtime changes
  • Render changes
  • Audio changes
  • Input changes
  • Network changes
  • Other changes

Description

Adds Android as a supported platform. Uses Gradle to perform the build overall.

Checklist

• I have tested my changes locally and verified that they work as intended.
• I have documented any new or modified functionality.
• I have reviewed the changes to ensure they do not introduce any unnecessary complexity or duplicate code.
• I understand that by submitting this pull request, I am agreeing to license my contributions under the project's license.

[Lgt2x]

Just a suggestion... You can add the __LINUX__ define for android platforms instead of adding it to every check

[tophyr]

Just a suggestion... You can add the __LINUX__ define for android platforms instead of adding it to every check

SDL specifically undefines __LINUX__ when ANDROID is defined, unfortunately.

[tophyr]

Ready for review.

Includes #493, #492, #469, and #465 as dependencies (see merge commit at base). Those PRs should be reviewed and merged prior to this one; marking this PR as a draft until then.