Corrected misuse of "formation" vs. "training"
Corrected "developpment" for "development"
Removed explanation about "formation" and added it to this commit.

"formation" is used for jet fighters or soldiers. ie: "Get back in formation" use "training" instead
Merge branch 'master' of github.com:idealtech/ProjetFormation
fixed gitignore
Merge branch 'master' of github.com:idealtech/ProjetFormation