Version 0.8.4 updates

In version 0.8.4 following major bugs have been fixed:

- Now in Windows Vista even if UAC (User Account Control) is switched on, Cayra can be installed successfully.

- Recent files list is updated immediately.

- During installation the version of .NET Framework 2.0 and 3.0 is checked. If there's no Framework installed, message box is shown.

- No problems with saving files.