Add cylon-ble-scan and cylon-ble-info commands.

Adds `cylon-ble-scan` and `cylon-ble-info` commands to use noble's scanning code to search for BLE devices and display characteristics for a specific BLE device.

Note that use need to install cylon-ble using the `-g` option, and then run each commands under `sudo` like this:

```
$ sudo cylon-ble-scan
Starting scan.
Peripheral discovered!
  Name: 2B-785E
  UUID: cc360e85785e
  rssi: -80
```

```
$ sudo cylon-ble-info cc360e85785e
peripheral with UUID cc360e85785e found
  Local Name        = 2B-785E
  TX Power Level    = -10
  Service Data      = 
  Service UUIDs     = 22bb746f2ba075542d6f726568705327

services and characteristics:
1800 (Generic Access)
  2a00 (Device Name)
    properties  read, write
    value       32422d37383545 | '2B-785E'
...
```