README: add video link, also LLVM 9 has been released

Author: geofft

README.md

@@ -6,11 +6,10 @@ using safe abstractions around kernel interfaces and primitives.
 For more information on the motivation and goals for this project, check
 out [our presentation at Linux Security Summit North America
 2019](https://ldpreload.com/p/kernel-modules-in-rust-lssna2019.pdf)
-(recording coming soon on [LSSNA's
-website](https://lssna19.sched.com/event/RHaT)). We're immediately
-focusing on making this project viable for out-of-tree modules, but we
-also see this project as a testing ground for whether in-tree components
-could be written in Rust.
+and the [video on YouTube](https://www.youtube.com/watch?v=RyY01fRyGhM).
+We're immediately focusing on making this project viable for out-of-tree
+modules, but we also see this project as a testing ground for whether
+in-tree components could be written in Rust.
 
 There is a simple demo module in the hello-world directory, as well as
 various other examples in the tests/ directory.
@@ -52,8 +51,9 @@ or higher [to bind constants
 properly](https://github.com/rust-lang/rust-bindgen/issues/1316). If
 you're running kernel 5.0 or newer, [you'll need Clang
 9](https://github.com/fishinabarrel/linux-kernel-module-rust/issues/123)
-(currently the development release).  You may need to set the `CLANG`
-environment variable appropriately, e.g., `CLANG=clang-9`.
+(released September 2019), which adds support for `asm goto`.
+You may need to set the `CLANG` environment variable appropriately,
+e.g., `CLANG=clang-9`.
 
 ## Building hello-world