Introduce namespace langutil in liblangutil directory.

Also:
- Use {}-style list initialisation for SourceLocation construction
- Introduce new system includes
- Changes the API of the Scanner to take source as value (with move) as opposed to as a reference

libsolidity/ast/AST.h

@@ -23,8 +23,8 @@
 #pragma once
 
 
+#include <libsolidity/parsing/Token.h>
 #include <libsolidity/ast/ASTForward.h>
-#include <liblangutil/Token.h>
 #include <libsolidity/ast/Types.h>
 #include <libsolidity/ast/ASTAnnotations.h>
 #include <libsolidity/ast/ASTEnums.h>
@@ -58,6 +58,8 @@ class ASTConstVisitor;
 class ASTNode: private boost::noncopyable
 {
 public:
+	using SourceLocation = langutil::SourceLocation;
+
 	explicit ASTNode(SourceLocation const& _location);
 	virtual ~ASTNode();
 

libsolidity/ast/ASTJsonConverter.cpp

@@ -27,6 +27,7 @@
 #include <libsolidity/inlineasm/AsmPrinter.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {

libsolidity/ast/ASTJsonConverter.h

@@ -29,6 +29,11 @@
 #include <libsolidity/ast/ASTAnnotations.h>
 #include <json/json.h>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
@@ -120,7 +125,7 @@ private:
 		std::string const& _nodeName,
 		std::vector<std::pair<std::string, Json::Value>>&& _attributes
 	);
-	std::string sourceLocationToString(SourceLocation const& _location) const;
+	std::string sourceLocationToString(langutil::SourceLocation const& _location) const;
 	static std::string namePathToString(std::vector<ASTString> const& _namePath);
 	static Json::Value idOrNull(ASTNode const* _pt)
 	{

libsolidity/ast/ASTPrinter.cpp

@@ -28,6 +28,7 @@
 #include <boost/algorithm/string/join.hpp>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {

libsolidity/ast/Types.cpp

@@ -45,6 +45,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace

libsolidity/ast/Types.h

@@ -25,7 +25,7 @@
 #include <liblangutil/Exceptions.h>
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTEnums.h>
-#include <liblangutil/Token.h>
+#include <libsolidity/parsing/Token.h>
 
 #include <libdevcore/Common.h>
 #include <libdevcore/CommonIO.h>