Use curve 25519 for gpg keys

src/freedombone-adduser

 chmod 600 /home/$ADD_USERNAME/.gnupg/*
 
 # Generate a GPG key
-echo 'Key-Type: 1' > /home/$ADD_USERNAME/gpg-genkey.conf
-echo 'Key-Length: 4096' >> /home/$ADD_USERNAME/gpg-genkey.conf
+echo 'Key-Type: 9' > /home/$ADD_USERNAME/gpg-genkey.conf
 echo 'Subkey-Type: 1' >> /home/$ADD_USERNAME/gpg-genkey.conf
-echo 'Subkey-Length: 4096' >> /home/$ADD_USERNAME/gpg-genkey.conf
 echo "Name-Real:  $ADD_USERNAME" >> /home/$ADD_USERNAME/gpg-genkey.conf
 echo "Name-Email: $ADD_USERNAME@$HOSTNAME" >> /home/$ADD_USERNAME/gpg-genkey.conf
 echo 'Expire-Date: 0' >> /home/$ADD_USERNAME/gpg-genkey.conf

src/freedombone-base-email

 
     # Generate a GPG subkey
     # Here a 2048bit length is used to be compatible with yubikey
-    echo 'Key-Type: 1' > /home/$MY_USERNAME/gpg-genkey.conf
+    echo 'Key-Type: 9' > /home/$MY_USERNAME/gpg-genkey.conf
     echo "Key-Grip: $KEYGRIP" > /home/$MY_USERNAME/gpg-genkey.conf
     echo 'Subkey-Type: 1' >> /home/$MY_USERNAME/gpg-genkey.conf
-    echo 'Subkey-Length: 2048' >> /home/$MY_USERNAME/gpg-genkey.conf
     echo "subkey-Usage: $GPG_KEY_USAGE" > /home/$MY_USERNAME/gpg-genkey.conf
     echo "Name-Real:  $MY_NAME" >> /home/$MY_USERNAME/gpg-genkey.conf
     echo "Name-Email: $MY_EMAIL_ADDRESS" >> /home/$MY_USERNAME/gpg-genkey.conf
         fi
     else
         # Generate a GPG key
-        echo 'Key-Type: 1' > /home/$MY_USERNAME/gpg-genkey.conf
-        echo 'Key-Length: 4096' >> /home/$MY_USERNAME/gpg-genkey.conf
+        echo 'Key-Type: 9' > /home/$MY_USERNAME/gpg-genkey.conf
         echo 'Subkey-Type: 1' >> /home/$MY_USERNAME/gpg-genkey.conf
-        echo 'Subkey-Length: 4096' >> /home/$MY_USERNAME/gpg-genkey.conf
         echo "Name-Real:  $MY_NAME" >> /home/$MY_USERNAME/gpg-genkey.conf
         echo "Name-Email: $MY_EMAIL_ADDRESS" >> /home/$MY_USERNAME/gpg-genkey.conf
         echo 'Expire-Date: 0' >> /home/$MY_USERNAME/gpg-genkey.conf

src/freedombone-utils-backup

     # Generate a GPG key for backups
     BACKUP_KEY_EXISTS=$(gpg_key_exists "$MY_USERNAME" "$MY_NAME (backup key)")
     if [[ $BACKUP_KEY_EXISTS == "no" ]]; then
-        echo 'Key-Type: 1' > /home/$MY_USERNAME/gpg-genkey.conf
-        echo 'Key-Length: 4096' >> /home/$MY_USERNAME/gpg-genkey.conf
+        echo 'Key-Type: 9' > /home/$MY_USERNAME/gpg-genkey.conf
         echo 'Subkey-Type: 1' >> /home/$MY_USERNAME/gpg-genkey.conf
-        echo 'Subkey-Length: 4096' >> /home/$MY_USERNAME/gpg-genkey.conf
         echo "Name-Real:  $MY_NAME" >> /home/$MY_USERNAME/gpg-genkey.conf
         echo "Name-Email: $MY_EMAIL_ADDRESS" >> /home/$MY_USERNAME/gpg-genkey.conf
         echo "Name-Comment: backup key" >> /home/$MY_USERNAME/gpg-genkey.conf