android-support-v4 has been deprecated

[bkmgit]

android-support-v4 is used when building android binaries, but has been deprecated. Would it be worth supporting newer libraries for recent Android versions? If so, can make a pull request to do this.

This would affect also using build-tools 34 and greater, as build-tools 34 does not seem to contain dx, so regular Android builds fail.

[mgorges]

In principle, the entire Android build system needs replacing (as we still use ant and not Gradle), but I don't use Android or have the capacity to support such a major revision. @ddunsmuir might be able to help with reviewing things if you want to propose pull requests. Thanks.

[ddunsmuir]

This would indeed be a large update, but certainly beneficial. I work mostly with Android, but I am typically building for older devices. I do have new devices for testing and would do reviewing if you make this as a pull request. We would appreciate it.