We now document how to trigger a troubleshooting shell when booting a di-b ramdisk. Change-Id: Ief44347893fa81a7f2669143e1746a5ee99599af
Ramdisks are now built inside a chroot which is built by the normal image build process. Doing so improves our independence of the precise state of the build host. This fixes bug 1194055. Change-Id: Ibc254fbb9e7b404b5f38c1b35bcde8a4136e8e28