Updated: minor language change in R BYO notebook

Author: djarpin

r_bring_your_own/r_bring_your_own.ipynb

@@ -235,7 +235,7 @@
    "source": [
     "### Dockerfile\n",
     "\n",
-    "Smaller containers are preferred for Amazon SageMaker, so this container is kept minimal.  It simply starts with Ubuntu, installs R, mda, and plumber libraries, then adds `mars.R` and `plumber.R`, and finally runs `mars.R` when the entrypoint is launched.\n",
+    "Smaller containers are preferred for Amazon SageMaker as they lead to faster spin up times in training and endpoint creation, so this container is kept minimal.  It simply starts with Ubuntu, installs R, mda, and plumber libraries, then adds `mars.R` and `plumber.R`, and finally runs `mars.R` when the entrypoint is launched.\n",
     "\n",
     "```Dockerfile\n",
     "FROM ubuntu:16.04\n",