Add option to shutdown connection before joining threads

include/mtxclient/http/client.hpp

@@ -96,7 +96,7 @@ public:
         Client(const std::string &server = "", uint16_t port = 443);
 
         //! Wait for the client to close.
-        void close();
+        void close(bool force = false);
         //! Set the homeserver domain name.
         void set_user(const mtx::identifiers::User &user) { user_id_ = user; }
         //! Set the device ID.

lib/http/client.cpp

@@ -38,13 +38,17 @@ Client::set_server(const std::string &server)
 }
 
 void
-Client::close()
+Client::close(bool force)
 {
         // Destroy work object. This allows the I/O thread to
         // exit the event loop when there are no more pending
         // asynchronous operations.
         work_.reset();
 
+        // We close all open connections.
+        if (force)
+                shutdown();
+
         // Wait for the worker threads to exit.
         thread_group_.join_all();
 }