Improved plugin system:

- the user is asked at start wether to load or deny unregistered plugins, but can make it mind later in config->plugins
- added API and SVN numbers into required external plugin symbols
- user-defined plugin rules are dropped when a plugin changes (hash changes) or when the main executable changes.
- added new status flags (Plugin denied, missing API/SVN numbers)
- modified saveList()/loadList() to allow saving a list of rejected plugins as well.
- added methods in notifyBase and inherited classes to ask for plugin confirmation.

- adapted VOIP plugin to follow these new rules (API+SVN numbers). Other plugins should be adapted as well by addign the 
 missing symbols (RETROSHARE_PLUGIN_api and RETROSHARE_PLUGIN_revision).



git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@5529 b45a01b8-16f6-495d-af2f-9b41ad6348cc

retroshare-gui/src/gui/notifyqt.h

@@ -59,6 +59,7 @@ class NotifyQt: public QObject, public NotifyBase
 		virtual void notifyDownloadComplete(const std::string& fileHash);
 		virtual void notifyDownloadCompleteCount(uint32_t count);
 		virtual bool askForPassword(const std::string& key_details, bool prev_is_bad, std::string& password);
+		virtual bool askForPluginConfirmation(const std::string& plugin_filename, const std::string& plugin_file_hash);
 
 		/* Notify from GUI */
 		void notifyChatStyleChanged(int /*ChatStyle::enumStyleType*/ styleType);