message: Update .gitignore to exclude my build directories.
diff: -### Build dirs ###
  -build/
  -
  -### Docs dirs ###
  -doc/html/
  -doc/xml/
  -doc/latex/
  -doc/*.tag
  -
  -# Created by https://www.gitignore.io/api/c++,cmake
  -
  -### C++ ###
  -# Prerequisites
  -*.d
  -
  -# Compiled Object files
  -*.slo
  -*.lo
  -*.o
  -*.obj
  -
  -# Precompiled Headers
  -*.gch
  -*.pch
  -
  -# Compiled Dynamic libraries
  -*.so
  -*.dylib
  -*.dll
  -
  -# Fortran module files
  -*.mod
  -*.smod
  -
  -# Compiled Static libraries
  -*.lai
  -*.la
  -*.a
  -*.lib
  -
  -# Executables
  -*.exe
  -*.out
  -*.app
  -
  -### CMake ###
  -CMakeCache.txt
  -CMakeFiles
  -CMakeScripts
  -Makefile
  -cmake_install.cmake
  -install_manifest.txt
  -compile_commands.json
  -CTestTestfile.cmake
  -build
  +thrust/system/cuda/detail/.gitignore
  +*.bash
  +*.log
  +.p4config
  +run
  +build*
  doc/html
  discrete_voronoi.pgm
  