doc(README.md): move the hook execution into the preamble

Author: Aaron Schlesinger

README.md

@@ -12,14 +12,13 @@ This Deis component is currently in beta status, and we welcome your input! If y
 
 # About
 
-The builder is primarily a git server that responds to `git push`es from clients. When it receives a push, it takes the below high level steps in order.
+The builder is primarily a git server that responds to `git push`es by executing either the `git-receive-pack` or `git-upload-pack` hook. After it executes one of those hooks, it takes the following high level steps in order:
 
-1. Executes the `git-receive-pack` or `git-upload-pack` hooks (as appropriate)
-2. Calls `git archive` to produce a tarball (i.e. a `.tar.gz` file) on the local file system
-3. Saves the tarball to centralized object storage according to the following rules:
+1. Calls `git archive` to produce a tarball (i.e. a `.tar.gz` file) on the local file system
+2. Saves the tarball to centralized object storage according to the following rules:
 	- If the `DEIS_OUTSIDE_STORAGE` environment variable exists, saves to the [S3 API][s3-api-ref] compatible server at `https://$DEIS_OUTSIDE_STORAGE`
   - Otherwise, if the `DEIS_MINIO_SERVICE_HOST` and `DEIS_MINIO_SERVICE_PORT` environment variables exist (these are standard [Kubernetes service discovery environment variables](http://kubernetes.io/docs/user-guide/services/#environment-variables)), saves to the [S3 API][s3-api-ref] compatible server at `http://$DEIS_MINIO_SERVICE_HOST:$DEIS_MINIO_SERVICE_HOST`
-4. Starts a new [Kubernetes Pod](http://kubernetes.io/docs/user-guide/pods/) to build the code, according to the following rules:
+3. Starts a new [Kubernetes Pod](http://kubernetes.io/docs/user-guide/pods/) to build the code, according to the following rules:
   - If a `Dockerfile` is present in the codebase, starts a [`dockerbuilder`](https://github.com/deis/dockerbuilder) pod, configured to download the code to build from the URL computed in the previous step.
   - Otherwise, starts a [`slugbuilder`](https://github.com/deis/slugbuilder) pod, configured to download the code to build from the URL computed in the previous step.