Removed SDL_bool in favor of plain bool

We require stdbool.h in the build environment, so we might as well use the plain bool type.

If your environment doesn't have stdbool.h, this simple replacement will suffice:
typedef signed char bool;

test/testoverlay.c

@@ -156,7 +156,7 @@ static int window_h;
 static int paused = 0;
 static int done = 0;
 static int fpsdelay;
-static SDL_bool streaming = SDL_TRUE;
+static bool streaming = true;
 static Uint8 *RawMooseData = NULL;
 
 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
@@ -362,7 +362,7 @@ int main(int argc, char **argv)
                 nodelay = 1;
             } else if (SDL_strcmp(argv[i], "--nostreaming") == 0) {
                 consumed = 1;
-                streaming = SDL_FALSE;
+                streaming = false;
             } else if (SDL_strcmp(argv[i], "--scale") == 0) {
                 consumed = 2;
                 if (argv[i + 1]) {
@@ -524,7 +524,7 @@ int main(int argc, char **argv)
     displayrect.h = (float)window_h;
 
     /* Ignore key up events, they don't even get filtered */
-    SDL_SetEventEnabled(SDL_EVENT_KEY_UP, SDL_FALSE);
+    SDL_SetEventEnabled(SDL_EVENT_KEY_UP, false);
 
     /* Main render loop */
     frames = 0;