fix: moved around files, feat: finished ex2 of serie2 processus

processus/serie1/ex1.md

processus/serie1/ex2/.gitignore

processus/serie1/ex2/Makefile

processus/serie1/ex2/ex2.md

processus/serie1/ex2/prog.c

processus/serie1/ex3/.gitignore

processus/serie1/ex3/orphan/.gitignore

processus/serie1/ex3/orphan/Makefile

processus/serie1/ex3/orphan/orphan.c

processus/serie1/ex3/zombie/.gitignore

processus/serie1/ex3/zombie/Makefile

processus/serie1/ex3/zombie/figs/zombie.png

processus/serie1/ex3/zombie/zombie.c

processus/serie1/ex3/zombie/zombie.md

processus/serie1/ex4/.gitignore

processus/serie1/ex4/Makefile

processus/serie1/ex4/multi_process.c

processus/serie1/ex5/.gitignore

processus/serie1/ex5/Makefile

processus/serie1/ex5/multi_process.c