Help: improve install() documentation of argument ordering

Fixes #16362.

Help/command/install.rst

@@ -38,7 +38,21 @@ signatures that specify them.  The common options are:
 
 ``CONFIGURATIONS``
   Specify a list of build configurations for which the install rule
-  applies (Debug, Release, etc.).
+  applies (Debug, Release, etc.). Note that the values specified for
+  this option only apply to options listed AFTER the ``CONFIGURATIONS``
+  option. For example, to set separate install paths for the Debug and
+  Release configurations, do the following:
+
+  .. code-block:: cmake
+
+    install(TARGETS target
+            CONFIGURATIONS Debug
+            RUNTIME DESTINATION Debug/bin)
+    install(TARGETS target
+            CONFIGURATIONS Release
+            RUNTIME DESTINATION Release/bin)
+
+  Note that ``CONFIGURATIONS`` appears BEFORE ``RUNTIME DESTINATION``.
 
 ``COMPONENT``
   Specify an installation component name with which the install rule