title: How to config cmake for strip file
body: <p>when I use cmake in Release mode I have the following binary:</p>
  
  <pre><code>64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=485ac09b0a3aa879f88b7f5db6c00ea8d8e1eaf6, not stripped
  </code></pre>
  
  <p>I want the binary to be stripped.
  How can I say to cmake in a clean way to add the -s option to my compiler to make it stripped?</p>
  
  <p>Why did the Default Release mode not strip my binary?</p>