Make JsEngine::Evaluate() return a wrapper for v8::Value to accessdifferent variable types easily

include/AdblockPlus/JsEngine.h

 #ifndef ADBLOCKPLUS_JS_ENGINE_H
 #define ADBLOCKPLUS_JS_ENGINE_H
 
 #include <stdexcept>
 #include <string>
 #include <v8.h>
 #include <AdblockPlus/JsValue.h>
 
 namespace AdblockPlus
 {
@@ skipping 22 matching lines @@
     void Gc();
     JsValuePtr NewValue(const std::string& val);
     JsValuePtr NewValue(int64_t val);
     JsValuePtr NewValue(bool val);
     inline JsValuePtr NewValue(const char* val)
     {
       return NewValue(std::string(val));
     }
     inline JsValuePtr NewValue(int val)
     {
-      return NewValue((int64_t)val);
+      return NewValue(static_cast<int64_t>(val));
     }
 
     class Context
     {
     public:
       Context(const JsEngine& jsEngine);
       virtual inline ~Context() {};
 
     private:
       const v8::Locker locker;
       const v8::HandleScope handleScope;
       const v8::Context::Scope contextScope;
     };
 
   private:
     const FileSystem* const fileSystem;
     v8::Isolate* isolate;
     v8::Persistent<v8::Context> context;
   };
 }
 
 #endif