Revert "Make SW UAC friendly"

This reverts commit bf5cb11fac9b3fca0ca61dc586e4a74749188919.
Make SW UAC friendly

* Edited the installer/uninstaller to support UAC:
    * If the user clicks "No" in the UAC prompt, the install folder will be automatically changed to "X:\Users\[User Name]\AppData\Roaming\Subtitle Workshop"
    * In the same situation, if the user tries to change the install folder to a folder that needs admin permissions, the installer will show a message dialog informing the user of that fact, not allowing the install to progress
    * The uninstaller will check if admin permissions are needed, if that's not the case, it won't show an UAC prompt

* Fixed a few bugs in the installer code:
    * The "Help" folder would be created in Start Menu even if you didn't select any manual during the install
    * The shortcuts for the manuals had the wrong path ($INSTDIR\Manual instead of $INSTDIR\Help) and had invalid values for icons
    * The working dir for executables' shortcuts would be set to the last value used for SetOutPath, this could cause some problems, so I made sure to set the right value before creating any shortcuts

* I tried to add a few more name/dir constants and make sure the existing ones were used across the entire code.