Fix Win32 headers for SHGetFolderPath() (MinGW 4.7 removed it from <shlwapi.h>).
Removed deprecated qVariantValue() and qVariantCanConvert() calls.
Change NSIS script to use "libraries.list" for list of files to install/delete (closes issue #6).
Ignore extra Win32 build scripts.
[Qt5] Use "widgets" module is Qt version is 5 or above.