FeedReader:

- Added error handling to xml functions
- Added xslt transformation
- Added retransform of existing messages
- Redesigned preview dialog
- Enabled embed images for forum feeds
- Changed config format, switching back to an older version results in a loss of all data of the FeedReader

Added new base class RSPlainTextEdit with placeholder text.
New library libxslt needed

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@6081 b45a01b8-16f6-495d-af2f-9b41ad6348cc

plugins/FeedReader/gui/FeedReaderMessageWidget.h

@@ -52,6 +52,7 @@ private slots:
 	void processFeed();
 	void openLinkMsg();
 	void copyLinkMsg();
+	void retransformMsg();
 
 	/* FeedReaderNotify */
 	void feedChanged(const QString &feedId, int type);