jsoncpp: update to current version 1.8.0; align Makefile.am

Re-split into original files and use original directory structure.
Files are picked from https://github.com/open-source-parsers/jsoncpp


Origin commit data
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Branch: ni/coolstream
Commit: 760a64fc6a
Author: vanhofen <vanhofen@gmx.de>
Date: 2017-03-28 (Tue, 28 Mar 2017)

Origin message was:
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- jsoncpp: update to current version 1.8.0; align Makefile.am

Re-split into original files and use original directory structure.
Files are picked from https://github.com/open-source-parsers/jsoncpp


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This commit was generated by Migit

lib/jsoncpp/include/json/forwards.h

@@ -0,0 +1,37 @@
+// Copyright 2007-2010 Baptiste Lepilleur
+// Distributed under MIT license, or public domain if desired and
+// recognized in your jurisdiction.
+// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
+
+#ifndef JSON_FORWARDS_H_INCLUDED
+#define JSON_FORWARDS_H_INCLUDED
+
+#if !defined(JSON_IS_AMALGAMATION)
+#include "config.h"
+#endif // if !defined(JSON_IS_AMALGAMATION)
+
+namespace Json {
+
+// writer.h
+class FastWriter;
+class StyledWriter;
+
+// reader.h
+class Reader;
+
+// features.h
+class Features;
+
+// value.h
+typedef unsigned int ArrayIndex;
+class StaticString;
+class Path;
+class PathArgument;
+class Value;
+class ValueIteratorBase;
+class ValueIterator;
+class ValueConstIterator;
+
+} // namespace Json
+
+#endif // JSON_FORWARDS_H_INCLUDED