MycroftOS: Implementation of a very first initial bootable version

- Add Buildroot patches to downgrade / upgrade package dependencies
  in line with the Mycroft A.I. software stack requirements.
- Add buildroot additional package dependencies in line with the
  Mycroft A.I. software stack requirements.
- Update rpi3 defconfig file.
- Implement initial root_fs overlay filestructure.
- Addition of some quick and dirty helper scripts.
- Update of README to reflect these changes.

scripts/br-patches.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+set -e
+
+for patch_file in buildroot-patches/*; do
+      patch -d buildroot/ -p1 < ${patch_file};
+done