Shutter 4.9: prenos za Windows

Shutter 4.9 has been released.
This update rebuilds Network Usage monitoring around a newer Windows API, keeps Shutter accurate on machines that stay running for months, and tightens a handful of reliability edges around averaged events, port checks, and presets.
The standout work is the Network Usage event. On Windows Vista and newer, network devices are now identified by a unique GUID instead of a MAC address, which can be missing, duplicated across virtual adapters, or spoofed. Traffic counters are 64-bit, so high-volume links no longer wrap. On older Windows the previous API is still used, and existing presets keep working as they are. If an adapter resets or its device index changes while Shutter is watching it, the same interface is found again instead of silently tracking the wrong one or none at all.

Other changes:
- Internal timers now use 64-bit ticks, so duration checks stay correct beyond 49.7 days of continuous uptime.
- Network Port checks cope better with brief socket errors, so a momentary glitch is less likely to be treated as a real open or closed state.
- Fixed a rare "List capacity is insufficient" error on events that use the average measurement option.
- The GUID and MAC address are shown next to the device description.
- Rates below 10 KB/s are shown as fractions.
- You can browse to the Presets folder even when it is still empty.
- Automatic migration of user data from VirtualStore has been dropped.
- Online help links now point at the current documentation platform.
- Upgraded build environment, plus general optimizations around version info and delayed event handling.
For more details see the full changelog between versions 4.8 and 4.9.