Update jsonrpc dependencies and rewrite dapps to futures. (#6522)

* Bump version.

* Fix RPC crate.

* Fix BoxFuture in crates.

* Compiles and passes tests!

* Get rid of .boxed()

* Fixing issues with the UI.

* Remove minihttp. Support threads.

* Reimplement files serving to do it in chunks.

* Increase chunk size.

* Remove some unecessary copying.

* Fix tests.

* Fix stratum warning and ipfs todo.

* Switch to proper branch of jsonrpc.

* Update Cargo.lock.

* Update docs.

* Include dapps-glue in workspace.

* fixed merge artifacts

* Fix test compilation.

dapps/src/tests/api.rs

@@ -49,6 +49,7 @@ fn should_handle_ping() {
 		"\
 			POST /api/ping HTTP/1.1\r\n\
 			Host: home.parity\r\n\
+			Content-Type: application/json\r\n\
 			Connection: close\r\n\
 			\r\n\
 			{}