blue-merle: provide a somewhat interactive way to set a new IMEI via SSH

This can currently only provide a random IMEI only. But we could easily
recover the deleted script. But it'd be nicer to have a central
configuration for the mode.

files/usr/bin/blue-merle

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+
+echo "Preparing SIM Swap..."
+/usr/bin/blue-merle-switch-stage1
+
+echo "Replace the SIM card, then press Enter"
+read answer
+
+echo "Continuing..."
+/usr/bin/blue-merle-switch-stage2
+
+echo "The device will shutdown. You should change the location before booting again."