turn HiisiEngine into a regular solib instead of built module

hiisi/hiisi.h

@@ -1,25 +1,17 @@
 #ifndef HIISI_H_
 #define HIISI_H_
 
-extern "C" {
+class HiisiEngine {
+  public:
+    int init(int argc, char *argv[]);
+    int event();
+    int iterate();
+    void quit();
 
-    struct EngineData {
-        void *window = 0;
-        void *renderer = 0;
-    };
+  private:
+    void *_window = 0;
+    void *_renderer = 0;
+    void *_module = 0;
+};
 
-    struct Engine {
-        void *module = 0;
-        int (*init)(EngineData *, int, char**);
-        int (*event)(EngineData *);
-        int (*iterate)(EngineData *);
-        void (*quit)(EngineData *);
-    };
-
-    int init(EngineData *state, int argc, char *argv[]);
-    int event(EngineData *state);
-    int iterate(EngineData *state);
-    void quit(EngineData *state);
-
-}
 #endif // HIISI_H_