Add report update mechanism

[SaschaWillems]

Newer versions of the client tool with updated headers may add new data (e.g. extension features and properties). Without a way to update existing reports, there is no way to get that data into the database unless a newer driver shows up.

The client tool should use the database mechanisms for checking if a report can be updated and let the user update it.

Refs SaschaWillems/vulkan.gpuinfo.org#31