Update description website in Cargo.toml

Update the description website to accurately capture the www subdomain.

Author: alexcameron89

capstone-rs/Cargo.toml

@@ -2,7 +2,7 @@
 authors = ["m4b <m4b.github.io@gmail.com>",
            "Richo Healey <richo@psych0tik.net>",
            "Travis Finkenauer <tmfinken@gmail.com>"]
-description = "High level bindings to capstone disassembly engine (https://capstone-engine.org/)"
+description = "High level bindings to capstone disassembly engine (https://www.capstone-engine.org/)"
 keywords = ["disassemble"]
 license = "MIT"
 name = "capstone"