Generate wrapper aliases only if requested and not by default

Defining the aliases by default results in conflicts when including
headers from multiple modules as e.g. SWIG_PendingException_get() is
defined in all of them, and could also easily result in other unwanted
clashes, so make this opt-in and update the examples and tests relying
on using the wrappers without the module prefix to define
SWIG_DEFINE_WRAPPER_ALIASES explicitly.

Examples/test-suite/c/c_backend_cpp_exception_runme.c

@@ -1,4 +1,6 @@
 #include <assert.h>
+
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "c_backend_cpp_exception/c_backend_cpp_exception_wrap.h"
 
 int main()

Examples/test-suite/c/c_backend_cpp_natural_std_string_runme.c

@@ -1,6 +1,8 @@
 #include <stdlib.h>
 #include <assert.h>
 #include <string.h>
+
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "c_backend_cpp_natural_std_string/c_backend_cpp_natural_std_string_wrap.h"
 
 int main()

Examples/test-suite/c/char_strings_runme.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "char_strings/char_strings_wrap.h"
 
 int main() {

Examples/test-suite/c/cpp_basic_runme.c

@@ -1,3 +1,4 @@
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "cpp_basic/cpp_basic_wrap.h"
 #include <assert.h>
 #include <stdio.h>

Examples/test-suite/c/cpp_basic_template_function_runme.c

@@ -1,4 +1,6 @@
 #include <assert.h>
+
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "cpp_basic_template_function/cpp_basic_template_function_wrap.h"
 
 int main() {

Examples/test-suite/c/enums_runme.c

@@ -1,6 +1,7 @@
 #include <assert.h>
 #include <stdlib.h>
 
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "enums/enums_wrap.h"
 
 int main() {

Examples/test-suite/c/exception_order_runme.c

@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "exception_order/exception_order_wrap.h"
 
 int main() {

Examples/test-suite/c/global_vars_runme.c

@@ -4,7 +4,7 @@
 
 int main(int argc, const char *argv[])
 {
-    init();
+    global_vars_init();
 
     assert(strcmp(b_get(), "string b") == 0);
     assert(x == 1234);

Examples/test-suite/c/li_std_pair_runme.c

@@ -1,3 +1,4 @@
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "li_std_pair/li_std_pair_wrap.h"
 #include <assert.h>
 

Examples/test-suite/c/operator_overload_runme.c

@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#define SWIG_DEFINE_WRAPPER_ALIASES
 #include "operator_overload/operator_overload_wrap.h"
 
 #define assert(x,msg) if (!x) { printf("%d: %s\n", x, msg); exit(1); }