Removed socket mutexes. Added more tests. Improved examples.

Socket mutexes are no longer really required, and so have been removed.

Added more tests for network encoding functions, and the URL parser.

The URL parser now returns a path preceeded with a '/' instead of cutting it out. Added get_uri() to URL, for getting the whole URI, so users don't have to concat it themselves from the more specialised functions.

Fixed default socket connect timeout checking for the wrong value.

Fixed request_type_strings not containing all of the possible request types.

Fixed README using old socket close syntax.

Cleaned up the examples a bit.

examples/simple_server_and_client/SimpleHttpClient.cpp

@@ -0,0 +1,54 @@
+//
+// Created by fred.nicolson on 01/02/18.
+//
+
+#include <iostream>
+#include <frnetlib/TcpSocket.h>
+#include <frnetlib/HttpRequest.h>
+#include <frnetlib/URL.h>
+#include <frnetlib/HttpResponse.h>
+
+int main()
+{
+    //Get an address to query from stdin
+    std::string url;
+    std::cout << "Enter URL: ";
+    std::cin >> url;
+
+    //Parse it into something easy to use
+    fr::URL parsed_url(url);
+    if(parsed_url.get_port().empty())
+    {
+        std::cerr << "No schema or port specified. Unable to connect." << std::endl;
+        return EXIT_FAILURE;
+    }
+
+    //Try to connect to the parsed address
+    fr::TcpSocket socket;
+    if(socket.connect(parsed_url.get_host(), parsed_url.get_port(), {}) != fr::Socket::Success)
+    {
+        std::cerr << "Failed to connect to the specified URL" << std::endl;
+        return EXIT_FAILURE;
+    }
+
+    //Construct a request, requesting the user provided URI
+    fr::HttpRequest request;
+    request.set_uri(parsed_url.get_uri());
+    if(socket.send(request) != fr::Socket::Success)
+    {
+        std::cerr << "Failed to send HTTP request" << std::endl;
+        return EXIT_FAILURE;
+    }
+
+    //Now wait for a response
+    fr::HttpResponse response;
+    if(socket.receive(response) != fr::Socket::Success)
+    {
+        std::cerr << "Failed to receive HTTP response" << std::endl;
+        return EXIT_FAILURE;
+    }
+
+    //Print out the response body
+    std::cout << response.get_body() << std::endl;
+
+}