Add instructions for Cygwin targets
Add instructions for Cygwin targets

c-owens/windows,c-owens/windows,samepage-labs/windows-templates,samepage-labs/windows-templates,StefanScherer/windows,StefanScherer/windows,ambakshi/windows,TaylorMonacelli/boxcutter-windows,quarkslab/windows,ambakshi/windows,HirotakaKato/boxcutter-windows-ja,MSumulong/windows,seancoyne/windows,boxcutter/windows,MSumulong/windows,MSumulong/windows,boxcutter/windows,TaylorMonacelli/boxcutter-windows,boxcutter/windows,TaylorMonacelli/boxcutter-windows,MYOB-Technology/packer-sqlserver,quarkslab/windows,TaylorMonacelli/boxcutter-windows,seancoyne/windows,ambakshi/windows,c-owens/windows,samepage-labs/windows-templates,StefanScherer/windows,HirotakaKato/boxcutter-windows-ja,seancoyne/windows,HirotakaKato/boxcutter-windows-ja,quarkslab/windows