usertools: add new telemetry script

usertools: add new telemetry script

This patch adds a python script that can be used with the new telemetry
socket. It connects as a client to the socket, and allows the user send
a command and see the JSON response.

The example usage below shows the script connecting to the new telemetry
socket, and sending three default telemetry commands entered by the user.
The response for each command is shown below the user input.

Connecting to /var/run/dpdk/rte/dpdk_telemetry.v2
{"version": "DPDK 20.05.0-rc0", "pid": 32794, "max_output_len": 16384}
--> /
{"/": ["/", "/help", "/info"]}
--> /info
{"/info": {"version": "DPDK 20.05.0-rc0", "pid": 32794, \
    "max_output_len": 16384}}
--> /help,/info
{"/help": {"/info": "Returns DPDK Telemetry information. \
    Takes no parameters"}}

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Ciara Power <ciara.power@intel.com>
Reviewed-by: Keith Wiles <keith.wiles@intel.com>