many changes, see description [skip ci]

Note: currently only works via manual injection, Rundll32Entry has been removed

- Fixed conflict with UpdatePack7R2 (and WuaCpuFix) by hooking `RegQueryValueExW` and fixing the path to `wuaueng.dll`. (fixes #100)
- Eliminated lots of redundant and unnecessary code.
- Other reliability improvements and bug fixes.
- Removed the error message that displays in the installers when `wuaueng.dll` is below the minimum supported version, and added an internal check that will skip the patching procedure if the version of `wuaueng.dll` is too low. **This means you can now safely install wufuc prior to any updates, and it will automatically start working once it's needed, without any potential side effects.** (fixes #99)
- Added `/UNATTENDED` flag to the batch installer and uninstaller. You can use this to bypass the confirmation for a fully automated installation/uninstallation. To use it, you invoke the batch script from an elevated command prompt, like so: `"wufuc_installer.bat" /UNATTENDED`
- Improved logging framework to allow multiple processes to safely write to the same `.log` file.

wufuc.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 15
-VisualStudioVersion = 15.0.26430.14
+VisualStudioVersion = 15.0.26730.15
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "wufuc", "wufuc\wufuc.vcxproj", "{00F96695-CE41-4C2F-A344-6219DFB4F887}"
 EndProject
@@ -44,4 +44,7 @@ Global
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {5070ABC4-3344-4D6E-B744-E3508B10A327}
+	EndGlobalSection
 EndGlobal