Release 1.2.0 request

Summary of changes:

• Added import and export support. txt and xml formats are supported (xml format similar to SIInformer). 
• Added google back-up. Now the content is synchronized between your devices. Not guaranteed, "backup" and "restore" must be enabled in device settings.
• Added possibility to add authors from budclub.ru
• Support for interactive download folder choosing.
• Fixed author removal. Now all related publications are removed as well.