examples: Move non-block socket examples to a single app

To simplify the examples, reused the boiler plate and statics and mainly
for testing on localhost interface with no physical network.

examples/protocols/sockets/non_blocking/example_test.py

@@ -0,0 +1,26 @@
+# This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+# Unless required by applicable law or agreed to in writing, this
+# software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, either express or implied.
+
+# -*- coding: utf-8 -*-
+
+from __future__ import print_function, unicode_literals
+
+import re
+
+import ttfw_idf
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_GENERIC')
+def test_examples_protocol_socket_non_block(env, _):
+    dut = env.get_dut('non_blocking_socket', 'examples/protocols/sockets/non_blocking', dut_class=ttfw_idf.ESP32DUT)
+
+    # start the test and expect the client to receive back it's original data
+    dut.start_app()
+    dut.expect(re.compile(r'nonblocking-socket-client: Received: GET / HTTP/1.1'), timeout=30)
+
+
+if __name__ == '__main__':
+    test_examples_protocol_socket_non_block()