Resolve Symbolic Link (if any) after choosing folder.
Hardcode the starting folder to be /sdcard/

Prevents users from choosing /storage/emulated/0/ which is linked to
the sdcard but is not a symbolic link. Therefore, it will "not exist"
when booting up the system.
Revert "Resolve Symbolic Link (if any) after choosing folder."

This reverts commit f502af654d8b2d9ff814ccf4abb5efb0367a4f5b.
Show Warning if Emulated path is selected

emulated path is due to the multi-user introduced in Android 4.2 and
above.
Documentations for hardcoded sdcard path