Update copyright dates

include/beast/core/prepare_buffer.hpp

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2013-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2013-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
@@ -18,7 +18,7 @@ namespace beast {
     The returned buffer points to the same memory as the
     passed buffer, but with a size that is equal to or less
     than the size of the original buffer.
-    
+
     @param n The size of the returned buffer.
 
     @param buffer The buffer to shorten. Ownership of the
@@ -43,7 +43,7 @@ prepare_buffer(std::size_t n,
     The returned buffer points to the same memory as the
     passed buffer, but with a size that is equal to or less
     than the size of the original buffer.
-    
+
     @param n The size of the returned buffer.
 
     @param buffer The buffer to shorten. Ownership of the