Merge branch 'feature-porting-mingw' into 'develop'

doc/cross-compile-mingw.md

etc/config.csh/settings

etc/config.sh/mpi

etc/config.sh/settings

src/Allwmake

src/OSspecific/MSwindows/Allwmake

src/OSspecific/MSwindows/MSwindows.C

src/OSspecific/MSwindows/MSwindows.H

src/OSspecific/MSwindows/Make/files

src/OSspecific/MSwindows/Make/options

src/OSspecific/MSwindows/cpuInfo/cpuInfo.C

src/OSspecific/MSwindows/cpuInfo/cpuInfo.H

src/OSspecific/MSwindows/cpuTime/cpuTime.H

src/OSspecific/MSwindows/cpuTime/cpuTimeFwd.H

src/OSspecific/MSwindows/fileMonitor/fileMonitor.C

src/OSspecific/MSwindows/fileMonitor/fileMonitor.H

src/OSspecific/MSwindows/fileStat/fileStat.C

src/OSspecific/MSwindows/fileStat/fileStat.H

src/OSspecific/MSwindows/memInfo/memInfo.C

src/OSspecific/MSwindows/memInfo/memInfo.H