title: "assimp/config.h" not found, It's in the folder though
body: <p>I'm using Visual Studio 2019 to make a simple scene with OpenGL. The libraries and includes seem to be correctly configured since I can access the header files and the assimp folderstructure. 
  When I try to include any assimp headers though I get this error, the weird thing is that the file is in the folder. It is called "config.h.in" when removing the ".in" from the file I get the error code "E0011" in line 1016 of the "config.h" file. Which reads as follows</p>
  
  <pre><code>// ---------- All the Build/Compile-time defines ------------
  
  /** @brief Specifies if double precision is supported inside assimp
   *
   * Property type: Bool. Default value: undefined.
   */
  
  #cmakedefine ASSIMP_DOUBLE_PRECISION 1
  
  #endif // !! AI_CONFIG_H_INC
  
  </code></pre>
  
  <p>Those are lines 1009 to 1018, while the file is open in VS19 I get no error only when switching to another file. I get the error again.</p>
  
  <p><strong>EDIT.</strong> I did use CMake and VS to build the Library and .dll files</p>