Revert "Cleaned up cstdlib includes"

This reverts commit 7b21849487.

The commit was ill-advised in the first place and appears to cause issues
with the XCode build.

src/ai/contexts.cpp

@@ -61,6 +61,7 @@
 #include <boost/smart_ptr/intrusive_ptr.hpp>  // for intrusive_ptr
 #include <boost/smart_ptr/shared_ptr.hpp>  // for dynamic_pointer_cast, etc
 #include <cmath>                       // for sqrt
+#include <cstdlib>                     // for abs
 #include <ctime>                       // for time
 #include <iterator>                     // for back_inserter
 #include <ostream>                      // for operator<<, basic_ostream, etc

src/asserts.hpp

@@ -17,6 +17,7 @@
 #ifndef ASSERTS_HPP_INCLUDED
 #define ASSERTS_HPP_INCLUDED
 
+#include <cstdlib>
 #include <iostream>
 #include <csignal>
 

src/config.cpp

@@ -26,6 +26,7 @@
 #include "util.hpp"
 #include "utils/const_clone.hpp"
 
+#include <cstdlib>
 #include <cstring>
 #include <deque>
 #include <istream>

src/game_launcher.cpp

@@ -62,6 +62,7 @@
 #include <algorithm>                    // for copy, max, min, stable_sort
 #include <boost/optional.hpp>           // for optional
 #include <boost/tuple/tuple.hpp>        // for tuple
+#include <cstdlib>                     // for system
 #include <iostream>                     // for operator<<, basic_ostream, etc
 #include <utility>                      // for pair
 #include <SDL.h>                        // for SDL_INIT_JOYSTICK, etc

src/gui/core/notifiee.hpp

@@ -15,6 +15,8 @@
 #ifndef GUI_WIDGETS_AUXILIARY_NOTIFIEE_HPP_INCLUDED
 #define GUI_WIDGETS_AUXILIARY_NOTIFIEE_HPP_INCLUDED
 
+#include <cstdlib>
+
 namespace gui2
 {
 

src/lexical_cast.hpp

@@ -52,6 +52,7 @@
 
 #include "global.hpp"
 
+#include <cstdlib>
 #include <string>
 #include <sstream>
 #include <boost/mpl/set.hpp>

src/map/location.hpp

@@ -21,6 +21,7 @@ class config;
 class variable_set;
 
 #include <cmath>
+#include <cstdlib>
 #include <set>
 #include <string>
 #include <vector>

src/random_new.hpp

@@ -14,6 +14,7 @@
 #ifndef RANDOM_NEW_H_INCLUDED
 #define RANDOM_NEW_H_INCLUDED
 
+#include <cstdlib> //needed for RAND_MAX
 #include <boost/cstdint.hpp>
 
 using boost::uint32_t;

src/sdl/utils.hpp

@@ -23,6 +23,7 @@
 
 #include <SDL.h>
 
+#include <cstdlib>
 #include <iosfwd>
 #include <map>
 #include <string>

src/units/unit.cpp

@@ -63,6 +63,7 @@
 #pragma warning (pop)
 #endif
 #include <cassert>                     // for assert
+#include <cstdlib>                     // for rand
 #include <exception>                    // for exception
 #include <iterator>                     // for back_insert_iterator, etc
 #include <new>                          // for operator new

src/util.cpp

@@ -19,6 +19,7 @@
 
 #include "util.hpp"
 
+#include <cstdlib>
 template<>
 size_t lexical_cast<size_t, const std::string&>(const std::string& a)
 {

src/wesnoth.cpp

@@ -87,6 +87,7 @@
 #include <cerrno>                       // for ENOMEM
 #include <clocale>                      // for setlocale, LC_ALL, etc
 #include <cstdio>                      // for remove, fprintf, stderr
+#include <cstdlib>                     // for srand, exit
 #include <ctime>                       // for time, ctime, time_t
 #include <exception>                    // for exception
 #include <fstream>                      // for operator<<, basic_ostream, etc