code: @Nonnull
    public static ESuccess writeStream (@WillClose @Nonnull final OutputStream aOS,
                                        @Nonnull final String sContent,
                                        @Nonnull final Charset aCharset)
    {
      ValueEnforcer.notNull (sContent, "Content");
      ValueEnforcer.notNull (aCharset, "Charset");
  
      return writeStream (aOS, sContent.getBytes (aCharset));
    }
docs: Write bytes to an {@link OutputStream}.
  
  @param aOS
  The output stream to write to. May not be <code>null</code>. Is closed
  independent of error or success.
  @param sContent
  The string to be written. May not be <code>null</code>.
  @param aCharset
  The charset to be used, to convert the String to a byte array.
  @return {@link ESuccess}