title: spidermonkey mozjs-31.2.0: js-config.h didn't install - how do I fix it
body: <p>Building helloworld test program after installing mozjs fails with the following error: </p>
  
  <pre><code>/usr/local/include/mozjs-31/js/TypeDecls.h:23:23: fatal error: js-config.h: No such file or directory 
   #include "js-config.h" 
  </code></pre>
  
  <p>It is in my build directory: </p>
  
  <pre><code>mozjs-31.2.0/js/src/build_OPT.OBJ/dist/include/js-config.h 
  mozjs-31.2.0/js/src/build_OPT.OBJ/js/src/js-config.h 
  </code></pre>
  
  <p>but make install didn't transfer it. </p>
  
  <pre><code>$ js-config --cflags --libs 
  -std=gnu++0x -include /usr/local/include/mozjs-31/js/RequiredDefines.h -I/usr/local/include/mozjs-31 
  -L${libdir} -l${JS_LIBRARY_NAME}  -lm -ldl 
  
  $ uname -a 
  Linux greg-softsprocket 3.13.0-46-generic #77-Ubuntu SMP Mon Mar 2 18:23:39 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux 
  </code></pre>
  
  <p>Everything seemed to build and install without a problem. Can I just copy it to <code>/usr/local/include/mozjs-31</code>? Should I be downloading and building a different source? This one was <code>https://people.mozilla.org/~sstangl/mozjs-31.2.0.rc0.tar.bz2</code></p>
  
  <p>Thanks. </p>