Help: Restore docs that find_library considers LIB, not INCLUDE

Documentation updates in commit 02f527c66a (Find: Provide global
controls for the `NO_[]_PATH` call options, 2019-06-12,
v3.16.0-rc1~541^2) accidentally switched the `find_library`
documentation to mention `INCLUDE` where it should be `LIB`.

While at it, update `find_file` and `find_path` to mention
`INCLUDE` and `PATH` in the order they are considered.

Help/command/find_file.rst

@@ -17,7 +17,8 @@ find_file
 .. |CMAKE_XXX_PATH| replace:: :variable:`CMAKE_INCLUDE_PATH`
 .. |CMAKE_XXX_MAC_PATH| replace:: :variable:`CMAKE_FRAMEWORK_PATH`
 
-.. |SYSTEM_ENVIRONMENT_PATH_XXX| replace:: The directories in ``PATH`` and ``INCLUDE``.
+.. |SYSTEM_ENVIRONMENT_PATH_XXX| replace:: The directories in ``INCLUDE``
+   and ``PATH``.
 .. |SYSTEM_ENVIRONMENT_PATH_WINDOWS_XXX| replace:: On Windows hosts:
       ``<prefix>/include/<arch>`` if :variable:`CMAKE_LIBRARY_ARCHITECTURE`
       is set, and |SYSTEM_ENVIRONMENT_PREFIX_PATH_XXX_SUBDIR|.

Help/command/find_library.rst

@@ -17,7 +17,8 @@ find_library
 .. |CMAKE_XXX_PATH| replace:: :variable:`CMAKE_LIBRARY_PATH`
 .. |CMAKE_XXX_MAC_PATH| replace:: :variable:`CMAKE_FRAMEWORK_PATH`
 
-.. |SYSTEM_ENVIRONMENT_PATH_XXX| replace:: The directories in ``PATH`` and ``INCLUDE``.
+.. |SYSTEM_ENVIRONMENT_PATH_XXX| replace:: The directories in ``LIB``
+   and ``PATH``.
 .. |SYSTEM_ENVIRONMENT_PATH_WINDOWS_XXX| replace:: On Windows hosts:
       ``<prefix>/lib/<arch>`` if :variable:`CMAKE_LIBRARY_ARCHITECTURE`
       is set, and |SYSTEM_ENVIRONMENT_PREFIX_PATH_XXX_SUBDIR|.

Help/command/find_path.rst

@@ -17,7 +17,8 @@ find_path
 .. |CMAKE_XXX_PATH| replace:: :variable:`CMAKE_INCLUDE_PATH`
 .. |CMAKE_XXX_MAC_PATH| replace:: :variable:`CMAKE_FRAMEWORK_PATH`
 
-.. |SYSTEM_ENVIRONMENT_PATH_XXX| replace:: The directories in ``PATH`` and ``INCLUDE``.
+.. |SYSTEM_ENVIRONMENT_PATH_XXX| replace:: The directories in ``INCLUDE``
+   and ``PATH``.
 .. |SYSTEM_ENVIRONMENT_PATH_WINDOWS_XXX| replace:: On Windows hosts:
       ``<prefix>/include/<arch>`` if :variable:`CMAKE_LIBRARY_ARCHITECTURE`
       is set, and |SYSTEM_ENVIRONMENT_PREFIX_PATH_XXX_SUBDIR|.