[Doc] Update gitian build guide to debian 8.4.0

doc/gitian-building.md

@@ -47,7 +47,7 @@ You can also install Gitian on actual hardware instead of using virtualization.
 
 Create a new VirtualBox VM
 ---------------------------
-In the VirtualBox GUI click "Create" and choose the following parameters in the wizard:
+In the VirtualBox GUI click "New" and choose the following parameters in the wizard:
 
 ![](gitian-building/create_new_vm.png)
 
@@ -74,13 +74,6 @@ In the VirtualBox GUI click "Create" and choose the following parameters in the
 - File location and size: at least 40GB; as low as 20GB *may* be possible, but better to err on the safe side
 - Click `Create`
 
-Get the [Debian 8.x net installer](http://cdimage.debian.org/debian-cd/8.3.0/amd64/iso-cd/debian-8.3.0-amd64-netinst.iso) (a more recent minor version should also work, see also [Debian Network installation](https://www.debian.org/CD/netinst/)).
-This DVD image can be validated using a SHA256 hashing tool, for example on
-Unixy OSes by entering the following in a terminal:
-
-    echo "dd25bcdde3c6ea5703cc0f313cde621b13d42ff7d252e2538a11663c93bf8654  debian-8.3.0-amd64-netinst.iso" | sha256sum -c
-    # (must return OK)
-
 After creating the VM, we need to configure it.
 
 - Click the `Settings` button, then go to the `Network` tab. Adapter 1 should be attached to `NAT`.
@@ -102,6 +95,13 @@ After creating the VM, we need to configure it.
 
 - Click `Ok` twice to save.
 
+Get the [Debian 8.x net installer](http://cdimage.debian.org/debian-cd/8.4.0/amd64/iso-cd/debian-8.4.0-amd64-netinst.iso) (a more recent minor version should also work, see also [Debian Network installation](https://www.debian.org/CD/netinst/)).
+This DVD image can be validated using a SHA256 hashing tool, for example on
+Unixy OSes by entering the following in a terminal:
+
+    echo "7a6b418e6a4ee3ca75dda04d79ed96c9e2c33bb0c703ca7e40c6374ab4590748  debian-8.4.0-amd64-netinst.iso" | sha256sum -c
+    # (must return OK)
+
 Then start the VM. On the first launch you will be asked for a CD or DVD image. Choose the downloaded iso.
 
 ![](gitian-building/select_startup_disk.png)
@@ -160,6 +160,10 @@ To select a different button, press `Tab`.
 
 ![](gitian-building/debian_install_12_choose_disk.png)
 
+  - Partition Disks -> *All files in one partition*
+
+![](gitian-building/all_files_in_one_partition.png)
+
   - Finish partitioning and write changes to disk -> *Yes* (`Tab`, `Enter` to select the `Yes` button)
 
 ![](gitian-building/debian_install_14_finish.png)