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

scripts/build.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+set -e
+
+all_platforms=(rpi3)
+for platform in "${all_platforms[@]}"; do
+#	make -C buildroot BR2_EXTERNAL=../buildroot-external distclean
+#	make -C buildroot BR2_EXTERNAL=../buildroot-external mycroftos_${platform}_defconfig
+
+	# Optional if you need to change stuff, uncomment the next line.
+	# make -C buildroot BR2_EXTERNAL=../buildroot-external makemenuconfig 
+
+	make -C buildroot BR2_EXTERNAL=../buildroot-external 2>&1 | tee logs/buildroot_output.txt
+	cp -f buildroot/output/images/sdcard.img release/MycroftOS_${platform}.img
+done