[Box Backup] Boxi DLL dependencies

[Achim]

Hello Victor:

A couple of months ago, we indeed discussed using the Cygwin CPPUnit
packages, and that introduced the cygwin1.dll dependency. Chris has some
very good arguments why that is not a good idea, and he convinced me that
compiling CPPUnit myself is a better solution.

Latest builds have dependencies on exactly 3 DLLs (cygcppunit-1-12-1.dll,
mgwz.dll, mingwm10.dll) apart from the system libraries:

root@batman /usr/src/boxi.646
$ objdump.exe -p boxi.exe  | grep "DLL Name"
        DLL Name: KERNEL32.DLL
        DLL Name: ADVAPI32.DLL
        DLL Name: COMCTL32.DLL
        DLL Name: COMDLG32.DLL
        DLL Name: cygcppunit-1-12-1.dll
        DLL Name: GDI32.dll
        DLL Name: mgwz.dll
        DLL Name: mingwm10.dll
        DLL Name: msvcrt.dll
        DLL Name: OLE32.dll
        DLL Name: OLEAUT32.DLL
        DLL Name: SHELL32.DLL
        DLL Name: USER32.dll
        DLL Name: WS2_32.DLL
        DLL Name: WSOCK32.DLL