Vid pid details

[bridadan]

This is part of the solution to #165. The next step would take place in the base class which would be responsible for altering the device_type field.

This PR implements a mechanism for each OS (Windows, Linux, and Mac) to provide the Vendor ID and Product ID of the Mbed devices present on the system. These two data items are present in the results as vendor_id and product_id respectively.

Both the vendor_id and product_id fields should be displayed as a 4 character, lower case hex string.

FYI @theotherjimmy @jupe

Here is some sample output:

$ mbedls -j
[
    {
        "daplink_build": "Jan 11 2016 16:12:36",
        "daplink_url": "http://mbed.org/device/?code=07400221076061193824F764",
        "daplink_version": "0221",
        "device_type": "daplink",
        "directory_entries": [
            "DETAILS.TXT",
            "MBED.HTM"
        ],
        "mount_point": "/mnt/pci-0000_00_06_0-usb-0_3_1_1-scsi-0_0_0_0",
        "platform_name": "NUCLEO_F411RE",
        "platform_name_unique": "NUCLEO_F411RE[0]",
        "product_id": "374b",
        "serial_port": "/dev/ttyACM1",
        "target_id": "07400221076061193824F764",
        "target_id_mbed_htm": "07400221076061193824F764",
        "target_id_usb_id": "0671FF554856805087112815",
        "vendor_id": "0483"
    },
    {
        "daplink_auto_reset": "0",
        "daplink_automation_allowed": "1",
        "daplink_bootloader_crc": "0xb92403e6",
        "daplink_bootloader_version": "0244",
        "daplink_daplink_mode": "Interface",
        "daplink_git_sha": "0beabef8aa4b382809d79e98321ecf6a28936812",
        "daplink_hic_id": "97969900",
        "daplink_interface_crc": "0x434eddd1",
        "daplink_interface_version": "0246",
        "daplink_local_mods": "0",
        "daplink_overflow_detection": "1",
        "daplink_remount_count": "0",
        "daplink_unique_id": "0240000032044e4500257009997b00386781000097969900",
        "daplink_usb_interfaces": "MSD, CDC, HID",
        "daplink_version": "0246",
        "device_type": "daplink",
        "directory_entries": [
            "MBED.HTM",
            "DETAILS.TXT"
        ],
        "mount_point": "/mnt/pci-0000_00_06_0-usb-0_2_1_0-scsi-0_0_0_0",
        "platform_name": "K64F",
        "platform_name_unique": "K64F[0]",
        "product_id": "0204",
        "serial_port": "/dev/ttyACM0",
        "target_id": "0240000032044e4500257009997b00386781000097969900",
        "target_id_mbed_htm": "0240000032044e4500257009997b00386781000097969900",
        "target_id_usb_id": "0240000032044e4500257009997b00386781000097969900",
        "vendor_id": "0d28"
    }
]

[coveralls]

Coverage increased (+0.7%) to 80.347% when pulling 10f906a on bridadan:vid_pid_details into 0e5f95c on ARMmbed:master.

[theotherjimmy]

I think it's more pythonic to use None here.

[theotherjimmy]

I would like to use None here as well. I don't like string matching on "unknown" as an API.

[bridadan]

On second thought, `"unknown"` is completely unnecessary, I'll just leave it as `None`.

[theotherjimmy]

Tests look great!

[bridadan]

Thanks for the feedback, I'll get those changes in soon

[bridadan]

Changes pushed!

FYI I have firmware detection based on this working! When this gets merged I'll put up the firmware detection PR.

[theotherjimmy]

@bridadan Let's have that firmware detection PR.