Move the new Win32-specific UTF-8 <-> UTF-16 conversion functions
to the svn_utf namespace.

* subversion/include/private/svn_subr_private.h
  (svn_subr__win32_utf8_to_utf16, svn_subr__win32_utf16_to_utf8):
   Move prototypes from here to ...
* subversion/include/private/svn_utf_private.h
  (svn_utf__win32_utf8_to_utf16, svn_utf__win32_utf16_to_utf8): ... here.

* subversion/libsvn_subr/win32_xlate.c
  (svn_subr__win32_utf8_to_utf16, svn_subr__win32_utf16_to_utf8):
   Move implementation from here to ...
* subversion/libsvn_subr/utf.c
  (svn_utf__win32_utf8_to_utf16, svn_utf__win32_utf16_to_utf8): ... here.

* subversion/bindings/javahl/native/JNIUtil.cpp,
  subversion/libsvn_subr/cmdline.c,
  subversion/libsvn_subr/config_win.c,
  subversion/libsvn_subr/nls.c: Update uses.
  Include svn_utf_private.h instead of svn_subr_private.h for
  svn_utf__win32_utf8_to_utf16 and svn_utf__win32_utf16_to_utf8.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1534118 13f79535-47bb-0310-9956-ffa450edef68