Moving BBSim entrypoint in the cmd folder, building bbsimctl in the container

Change-Id: I4823578ed17c40b13c1c9a561e7aa7e6640f7f19
diff --git a/.gitignore b/.gitignore
index 8b13789..dbc2a92 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,4 @@
+vendor
 
+/bbsim
+/bbsimctl