Asynchronous HTTP Request and Promise

Changes for v0.3.1 - 2023-09-22T09:41:30Z

• Correcting a bug in method is_binary() in HTTP:😛romise::Entity affecting the content of the data being tested.
• Checking in method _read_body_chunked() in HTTP:😛romise that the length of data written to body file matches the expected amount or returns an error.