- Update to 2.9.1:
* usage of unsupportable linux_syscall_support.h has been
removed from few places.
* Incorrect assertion failure was fixed that crashed tcmalloc
if assertions were on and sized delete was used
* there is now better backtracing support for aarch64 and riscv
x86-64 with frame pointers now also defaults to this new
"generic" frame pointer backtracer.
- Use golang version of pprof
- Split doc into subpackage