Use C++17 to compile 0 A.D.

Supported compilers are Clang 5, GCC 7, Visual Studio 17, Xcode 9.3

Update Atlas alongside since the replacement APIs are c++17 only.
De-activate the StyledTextCtrl module of WxWidgets on mac, since that is
a wrapper around the Scintilla Text editor and doesn't compile with
C++17 (as it uses auto_ptr). We don't use the editor, so this is also a
win on the compilation time front.

Closes #5862

Differential Revision: https://code.wildfiregames.com/D3166
This was SVN commit r24308.

build/premake/premake5.lua

@@ -199,11 +199,11 @@ function project_set_build_flags()
 	-- being used as a DLL (which is currently not the case in 0ad)
 	defines { "LIB_STATIC_LINK" }
 
-	-- Enable C++14 standard.
+	-- Enable C++17 standard.
 	filter "action:vs*"
-		buildoptions { "/std:c++14" }
+		buildoptions { "/std:c++17" }
 	filter "action:not vs*"
-		buildoptions { "-std=c++14" }
+		buildoptions { "-std=c++17" }
 	filter {}
 
 	-- various platform-specific build flags

libraries/osx/build-osx-libs.sh

@@ -86,7 +86,7 @@ if [[ $MIN_OSX_VERSION && ${MIN_OSX_VERSION-_} ]]; then
 fi
 
 CFLAGS="$CFLAGS $C_FLAGS -fvisibility=hidden"
-CXXFLAGS="$CXXFLAGS $C_FLAGS -stdlib=libc++ -std=c++14 -msse4.1"
+CXXFLAGS="$CXXFLAGS $C_FLAGS -stdlib=libc++ -std=c++17 -msse4.1"
 OBJCFLAGS="$OBJCFLAGS $C_FLAGS"
 OBJCXXFLAGS="$OBJCXXFLAGS $C_FLAGS"
 
@@ -427,6 +427,7 @@ then
     --without-libtiff
     --without-sdl
     --without-x
+    --disable-stc
     --disable-webview
     --disable-webkit
     --disable-webviewwebkit

source/tools/atlas/AtlasUI/General/Observable.cpp

@@ -23,8 +23,8 @@ void ObservableScopedConnections::Add(const ObservableConnection& conn)
 {
 	// Clean up any disconnected connections that might be left in here
 	m_Conns.erase(
-		remove_if(m_Conns.begin(), m_Conns.end(),
-			not1(std::mem_fun_ref(&ObservableConnection::connected))),
+	    std::remove_if(m_Conns.begin(), m_Conns.end(),
+	        std::not_fn(std::mem_fn(&ObservableConnection::connected))),
 		m_Conns.end()
 	);
 
@@ -35,5 +35,5 @@ void ObservableScopedConnections::Add(const ObservableConnection& conn)
 ObservableScopedConnections::~ObservableScopedConnections()
 {
 	// Disconnect all connections that we hold
-	for_each(m_Conns.begin(), m_Conns.end(), std::mem_fun_ref(&ObservableConnection::disconnect));
+	for_each(m_Conns.begin(), m_Conns.end(), std::mem_fn(&ObservableConnection::disconnect));
 }

source/tools/atlas/AtlasUI/General/Observable.h

@@ -39,15 +39,9 @@ variable_to_be_watched.NotifyObservers();
 
 */
 
-#include <boost/bind.hpp>
-#include <boost/version.hpp>
-#if BOOST_VERSION >= 104000
-# include <boost/signals2.hpp>
+#include <boost/signals2.hpp>
 typedef boost::signals2::connection ObservableConnection;
 typedef boost::signals2::scoped_connection ObservableScopedConnection;
-#else
-# error Atlas requires Boost 1.40 or later
-#endif
 
 template <typename T> class Observable : public T
 {
@@ -63,7 +57,7 @@ public:
 
 	template<typename C> ObservableConnection RegisterObserver(int order, void (C::*callback) (const T&), C* obj)
 	{
-		return m_Signal.connect(order, boost::bind(std::mem_fun(callback), obj, _1));
+		return m_Signal.connect(order, std::bind(std::mem_fn(callback), obj, std::placeholders::_1));
 	}
 
 	ObservableConnection RegisterObserver(int order, void (*callback) (const T&))
@@ -135,7 +129,7 @@ public:
 
 	template<typename C> ObservableConnection RegisterObserver(int order, void (C::*callback) (T*), C* obj)
 	{
-		return m_Signal.connect(order, boost::bind(std::mem_fun(callback), obj, _1));
+		return m_Signal.connect(order, std::bind(std::mem_fn(callback), obj, std::placeholders::_1));
 	}
 
 	ObservableConnection RegisterObserver(int order, void (*callback) (T*))