Add Example for sending information to DB via UDP (influxdata#648)

Due to lack of documentation for UDP, this example
provides basic usage of sending information points
via UDP. The code structure followed is similar, if
not same as other examples in the `examples` directory.

Signed-off-by: Shantanoo <shantanoo.desai@gmail.com>

Author: shantanoo-desai

docs/source/examples.rst

@@ -25,3 +25,9 @@ Tutorials - SeriesHelper
 
 .. literalinclude:: ../../examples/tutorial_serieshelper.py
    :language: python
+
+Tutorials - UDP
+===============
+
+.. literalinclude:: ../../examples/tutorial_udp.py
+   :language: python

examples/tutorial_udp.py

@@ -0,0 +1,66 @@
+# -*- coding: utf-8 -*-
+"""Example for sending batch information to InfluxDB via UDP."""
+
+"""
+INFO: In order to use UDP, one should enable the UDP service from the
+`influxdb.conf` under section
+    [[udp]]
+        enabled = true
+        bind-address = ":8089" # port number for sending data via UDP
+        database = "udp1" # name of database to be stored
+    [[udp]]
+        enabled = true
+        bind-address = ":8090"
+        database = "udp2"
+"""
+
+
+import argparse
+
+from influxdb import InfluxDBClient
+
+
+def main(uport):
+    """Instantiate connection to the InfluxDB."""
+    # NOTE: structure of the UDP packet is different than that of information
+    #       sent via HTTP
+    json_body = {
+        "tags": {
+            "host": "server01",
+            "region": "us-west"
+        },
+        "time": "2009-11-10T23:00:00Z",
+        "points": [{
+            "measurement": "cpu_load_short",
+            "fields": {
+                "value": 0.64
+            }
+        },
+            {
+                "measurement": "cpu_load_short",
+                "fields": {
+                    "value": 0.67
+                }
+        }]
+    }
+
+    # make `use_udp` True and  add `udp_port` number from `influxdb.conf` file
+    # no need to mention the database name since it is already configured
+    client = InfluxDBClient(use_udp=True, udp_port=uport)
+
+    # Instead of `write_points` use `send_packet`
+    client.send_packet(json_body)
+
+
+def parse_args():
+    """Parse the args."""
+    parser = argparse.ArgumentParser(
+        description='example code to play with InfluxDB along with UDP Port')
+    parser.add_argument('--uport', type=int, required=True,
+                        help=' UDP port of InfluxDB')
+    return parser.parse_args()
+
+
+if __name__ == '__main__':
+    args = parse_args()
+    main(uport=args.uport)