Use a packaged zip binary instead of system zip

As some roms do not provide a zip tool (https://github.com/mar-v-in/freecyngn/issues/2), freecyngn should use its own zip binary.

Info-Zip is open source and can be compiled by oneself. There is a GitHub repository with a patch to get zip running on Android here: https://github.com/jruesga/android_external_zip