Improve the Windows download code
Improve the Windows download code

Mark dbghinst.EXE as executable (from Cygwin's point of view) if
necessary.

Warn that running the security fix installer containing gdiplus.dll
might cause a UAC prompt, and instruct the developer what to do. Be
more verbose in abnormal situations after running it.

Drop some pointless messages.

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core