update docs

src/com/sun/jna/NativeLibrary.java

@@ -58,6 +58,8 @@
  * resource will be extracted to <code>jna.tmpdir</code> for loading, and
  * later removed (but only if <code>jna.nounpack</code> is false or not set).
  * </ol>
+ * You may set the system property <code>jna.debug_load=true</code> to make
+ * JNA print the steps of its library search to the console.
  * @author Wayne Meissner, split library loading from Function.java
  * @author twall
  */

www/FrequentlyAskedQuestions.md

@@ -5,12 +5,16 @@ I'm having trouble generating correct library mappings
 ------------------------------------------------------
 Make sure you've read [this page](https://github.com/twall/jna/tree/master/www/Mappings.md) and [this one](http://twall.github.com/jna/3.4.0/javadoc/overview-summary.html#overview_description).  Try [JNAerator](http://code.google.com/p/jnaerator/).  If you find its output too verbose, delete the mappings you don't need, or copy out the ones you do need.
 
+Calling `Native.loadLibrary()` causes an UnsatisfiedLinkError
+-------------------------------------------------------------
+
+Set the system property `jna.debug_load=true`, and JNA will print its library search steps to the console.  `jna.debug_load.jna` will trace the search for JNA's own native support.
+
 My library mapping causes an UnsatisfiedLinkError
 -------------------------------------------------
 
 Use a dump utility to examine the names of your exported functions to make sure they match (nm on linux, [depends](http://www.dependencywalker.com/) on Windows). On Windows, if the functions have a suffix of the form "@NN", you need to pass a `StdCallFunctionMapper` as an option when initializing your library interface. In general, you can use a function mapper (`FunctionMapper`) to change the name of the looked-up method, or an invocation mapper (`InvocationMapper`) for more extensive control over the method invocation.
 
-
 How do I map a native `long` type?
 ----------------------------------