Fix typo in client.md

`cntl` is not a pointer here

Update benchmark.md

拼写错误吧？

make tools/ support cmake & modify docs/cn/getting_started.md to add cmake

support bazel build

make lib include bin into $PWD/output & make all example be able to be compiled by default

make lib include bin into /home/zhujiashun/brpc/output & make all example be able to be compiled by default