Add gitignore

 - Don't track some auto-generated file

.gitignore

@@ -0,0 +1,11 @@
+_build
+oclaunch.byte
+session.vim
+settings_j.ml
+settings_j.mli
+settings_t.ml
+settings_t.mli
+/bin/sh: g : commande introuvable
+.paths
+.project
+.settings/