Add libbzle - a small lib for BLE support from bluez.

libbzle packages bluez files required for Bluetooth LE functionality.
This allows the Anki Drive SDK examples to be built and run on Linux
without requiring users to download the latest BlueZ library.
Add support for running tests & installing build products.

- Run tests by typing 'make test' inside the build dir.

- Assemble build products by running 'make install' inside
the build dir.

This install build products locally under ./build/dist
unless the user specifies a custom install path.

build/dist/
├── bin
|	...
├── include
│   ├── ankidrive
|		...
│   └── bzle
│       ├── bluetooth
|			...
│       └── gatt
|			...
└── lib
	...