title: clang format: disable ordering includes
body: <p>In our C++ project, the order of our includes is regularly changed. This is a problem since we are using some third-party libraries which require a specific include order to avoid problems. </p>
  
  <p>I know, this is bad but we have to deal with it. </p>
  
  <p>Unfortunately, the order of our includes is regularly changed and I suppose that this is due to <code>clang-format</code>. I found a <a href="https://clang.llvm.org/docs/ClangFormatStyleOptions.html" rel="noreferrer">page</a> where you can specify a variable <code>includeCategories</code>. 
  However, I do not fully understand how it works. 
  I simply want to completely disable the ordering of includes. 
  How can I do this? </p>