Reverted resource references for combine_something, you can't use tool_image here, because on MSW that only works for .bmps'

Added dependency stuff to invalidate Choice images;
Fixed 'duplicate' in symbol editor

git-svn-id: svn://svn.code.sf.net/p/magicseteditor/code/trunk@197 0fc631ac-6414-0410-93d0-97cfa31319b6

src/data/field.hpp

@@ -102,7 +102,10 @@ class Style {
 	/// Update scripted values of this style, return true if anything has changed
 	virtual bool update(Context&);
 	/// Add the given dependency to the dependent_scripts list for the variables this style depends on
+	/** Only use for things that need invalidate() */
 	virtual void initDependencies(Context&, const Dependency&) const;
+	/// Invalidate scripted images for this style
+	virtual void invalidate() {}
 	
   private:
 	DECLARE_REFLECTION_VIRTUAL();