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.

appveyor.yml

@@ -12,11 +12,11 @@ build:
   verbosity: minimal
 before_build:
 - cmd: >-
-    set "BUILD_VERSION=%APPVEYOR_BUILD_VERSION%-%APPVEYOR_REPO_COMMIT:~0,8%"
+    set "BUILD_COMMIT_VERSION=%APPVEYOR_BUILD_VERSION%-%APPVEYOR_REPO_COMMIT:~0,8%"
 
-    set "BUILD_VERSION_COMMA_SEP=%APPVEYOR_BUILD_VERSION:.=,%"
+    set "BUILD_VERSION_COMMA=%APPVEYOR_BUILD_VERSION:.=,%"
 
-    set "BUILD_ZIPFILE=%APPVEYOR_BUILD_FOLDER%\%APPVEYOR_PROJECT_NAME%_v%BUILD_VERSION%_%PLATFORM%.zip"
+    set "BUILD_ZIPFILE=%APPVEYOR_BUILD_FOLDER%\%APPVEYOR_PROJECT_NAME%_v%BUILD_COMMIT_VERSION%_%PLATFORM%.zip"
 after_build:
 - cmd: >-
     copy /Y "wufuc\bin\%CONFIGURATION%\%PLATFORM%\wufuc*.dll" "setup-batch\"