[CTX] [ALL] external privileged commands

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Privileged operations without being superuser

Some operations of DeleGate needs the privilege of super-user, but running whole DeleGate process under super-user's ability is not desirable for security. To solve the problem, you can execute DeleGate by normal user while executing a privileged operation by a small external program with "set user ID on execution" flag. Those external subsidiary programs are placed at DGROOT/subin/ by optional installation.

dgpam -- to do PAM authentication (AUTHORIZER)

dgchroot -- to do chroot(2) (CHROOT)

dgbind -- to do bind(2) to privileged ports (-P, SRCIF, FTP data, SOCKS server)

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