dist: Add missing files
The dist zipfile we were generating didn't include the recovery image or the
README our prior build system generated through additional scripting.
diff --git a/README b/README
new file mode 100644
@@ -0,0 +1,15 @@
+These files are required to flash the Mendel Linux OS to an attached device
+1. On your host computer, install the `fastboot` tool.
+2. Using either the serial console or the `fastboot` tool, put the device into
+ fastboot mode.
+3. Connect to the device using a USB cable, attached to the device's USB data
+ "OTG" port.
+4. Run the `flash.sh` script in this directory.
+For detailed instructions, visit g.co/coral/setup
+Note: The recovery.img file is just the U-Boot image. Use that to recover a
+failing device by flashing it to an SD card and booting from that (also follow
+the previous link for details).
diff --git a/dist.mk b/dist.mk
index 4b47f88..78880dd 100644
@@ -30,9 +30,11 @@
+ $(PRODUCT_OUT)/recovery.img \
+ $(ROOTDIR)/board/flash.sh \