fix: on Android, do not exceed process limit

feat: use emacs android prefix for packages as well as termux

Since I cannot get termux working now, I have compiled
packages from termux with this pewfix for emacs...

feat: use emacs android prefix for packages as well as termux

Since I cannot get termux working now, I have compiled
packages from termux with this pewfix for emacs...

fix: use system-type, not window-system, it's nil for daemon

feat: add android setup