Fix bugs and make improvements to redbean

- Abort if .init.lua fails
- Refactor redbean to use new append library
- Use first certificate if SNI routing fails
- Use function/data sections when building Lua
- Don't use self-signed auto-generated cert for client
- Add -D staging dirs to redbean lua module default path

third_party/mbedtls/config.h

@@ -2,6 +2,7 @@
 #define MBEDTLS_CONFIG_H_
 #include "libc/dce.h"
 
+/* /\* uncomment for testing old cpu code paths *\/ */
 /* #include "libc/nexgen32e/x86feature.h" */
 /* #undef X86_HAVE */
 /* #define X86_HAVE(x) 0 */