title: CMakeLists.txt files for multiple libraries and executables
body: <p>I am just starting playing with CMake. I have something like:</p>
  
  <pre><code>/DEV
   |-- lib1
          | CMakeLists.txt
  
   |-- lib2
          | CMakeLists.txt
  
   |-- exe1
          | CMakeLists.txt
  
  /BUILD
   |-- lib1
   |-- lib2
   |-- exe1
  
  /INSTALL
   |-- include
   |-- lib
   |-- bin
  </code></pre>
  
  <p>I would like to:</p>
  
  <ul>
  <li>Build each lib and exe independently when needed. (So I suppose I must add a CMakeLists.txt file for each lib and exe);</li>
  <li>When building, include and lib directories should reference INSTALL directory; (is it a good idea?)</li>
  <li>When building, add dependencies to other lib and rebuild them if not up to date.</li>
  </ul>
  
  <p>I dont have any clue where to start. Please help...</p>