message: Update .gitignore based on similar NAS2D rules
diff: -*.dll
  -/data
  -/API
  -/proj/vc14/Debug
  -/proj/vc14/*.opendb
  -/proj/vc14/*.db
  -/proj/vc14/Release Gold
  -/proj/vc14/Release
  -/*.exe
  -/proj/vc14/.vs/OPHD/v14/*.suo
  -/*.log
  -/proj/vc14/*.user
  -/proj/vc14/StructureAligner/Release
  -/proj/vc14/StructureAligner/Debug
  -/proj/vc15/Debug
  -/proj/vc15/.vs
  -/proj/vc15/*.db
  -/proj/vc15/*.aps
  -/proj/vc15/*.suppress
  -/proj/vc15/Release Gold
  -/proj/vc15/Release
  -.build/
  +# All platforms
  +/data/
  +
  +# Linux - Makefile
  +/.build/
  OPHD
  -Debug
  -packages
  -Release Gold
  -.vs
  -/proj/vs2019/Release
  -/proj/vs2019/x64
  +
  +# Windows - Visual Studio
  +Release/
  +Debug/
  +x64/
  +.vs/
  +*.user
  