Link dowsing_target, eggException, d_lyt_meter_drink (#128)

* Link dowsing_target, eggException

* d_lyt_meter_drink OK (thanks Zeldex!)

* More sensible DowsingTarget flag code

* Attempt explaining TList inline

include/egg/core/eggVideo.h

@@ -30,7 +30,7 @@ public:
     static u32 getTickPerVRetrace();
     static const GXRenderModeObj *getStandardRenderModeObj(const RenderModeObjSet *);
 
-    GXRenderModeObj *getCurrentOrFallbackRenderModeObj() const {
+    const GXRenderModeObj *getCurrentOrFallbackRenderModeObj() const {
         if (pRenderMode == nullptr) {
             return &lbl_8055FC64;
         }

include/egg/util/eggException.h

@@ -21,7 +21,7 @@ public:
 
     static Exception *sException;
 
-    volatile static nw4r::db::ConsoleHandle sConsoleHandle;
+    static nw4r::db::ConsoleHandle sConsoleHandle;
     static void *sMapFileWorks;
     static u32 sMapFileNumMax;
     static u32 sCurrentMapFileNum;

include/nw4r/lyt/lyt_types.h

@@ -27,7 +27,7 @@ struct BitGXNums {
 template <typename T>
 inline bool TestBit(T bits, int index) {
     T mask = 1 << index;
-    return bits & mask;
+    return (bits & mask) != 0;
 }
 template <typename T>
 inline void SetBit(T *bits, int pos, bool val) {

include/toBeSorted/tlist.h

@@ -78,6 +78,21 @@ public:
         }
     }
 
+    /**
+     * Returns an iterator representing the position of pT in this
+     * list. If pT is not in the list, the result is the end iterator.
+     *
+     * This is typically used to check if an object is contained in a
+     * list of this type.
+     */
+    Iterator GetPosition(T *pT) {
+        if (pT->mLink.mpNext == nullptr || pT->mLink.mpPrev == nullptr) {
+            return GetEndIter();
+        } else {
+            return Iterator(pT);
+        }
+    }
+
     Iterator GetEndIter() {
         return Iterator(GetPtrFromNode(&mStartEnd));
     }