Situation: RegAlyzer does store a history of changes on the Change logs tab.

Experienced: currently you would have to copy the contents into a text editor, save as .reg there, and then execute to undo.

Expected: two things:
1. Button to save the changes to a .reg file;
2. Button to apply the changes (for undo only of course) - aka Undo function.

Save buttons implemented.

Apply buttons added; won't affect log contents currently. Suggest different
behaviour if you have better ideas.