Update notes

 * Update to ASDF 3.3.3
 * Note that gcc -O1 can build cmucl now for gcc 8.1.1 and later.
 * Added x86_linux_clang to build cmucl with clang on linux
2 jobs for master in 17 minutes and 48 seconds
Status Job ID Name Coverage
  Test
passed #1638
linux
linux-runner

00:17:48

passed #1639
osx
osx-runner

00:13:44