normalized source directory to $SRC_DIR

Change-Id: I6833a941312210f06763e45395495429793c0e42
diff --git a/docs/install.md b/docs/install.md
index 568f17b..f319aac 100644
--- a/docs/install.md
+++ b/docs/install.md
@@ -86,11 +86,11 @@
 
 The helm charts used to deploy XOS are currently bundled in the CORD
 `helm-chart` repository. The rest of this section assumes all you download
-this repository into a directory named `~/xos`.
+this repository into directory `$SRC_DIR`.
 
 ```shell
-mkdir ~/xos
-cd ~/xos
+mkdir $SRC_DIR
+cd $SRC_DIR
 git clone https://gerrit.opencord.org/helm-charts
 cd helm-charts
 ```
@@ -104,7 +104,7 @@
 ## Bring Up XOS
 
 To deploy `xos-core` (plus affiliated micro-services) into your
-Kubernetes cluster, execute the following from the `~/xos/helm-charts`
+Kubernetes cluster, execute the following from the `$SRC_DIR/helm-charts`
 directory:
 
 ```shell
@@ -131,7 +131,7 @@
 
 Optionally, you can bring up a simple service to be managed by XOS.
 This involves deploying two additional helm charts: `base-kubernetes`
-and `demo-simpleexampleservice`. Again from the `~/xos/helm-charts`
+and `demo-simpleexampleservice`. Again from the `$SRC_DIR/helm-charts`
 directory, execute the following:
 
 ```shell
@@ -174,7 +174,7 @@
 ```
 
 This will launch a window in your default browser. Administrator login
-and password are defined in `~/xos/helm-charts/xos-core/values.yaml`.
+and password are defined in `$SRC_DIR/helm-charts/xos-core/values.yaml`.
 
 ## Next Steps
 
diff --git a/docs/repo.md b/docs/repo.md
index c6a0c6d..62c2fa3 100644
--- a/docs/repo.md
+++ b/docs/repo.md
@@ -25,27 +25,15 @@
 
 ## Download Repositories
 
-The XOS repositories are usually checked out to `~/xos` in most of our
-examples:
+We assume the XOS repositories are checked out into directory `$SRC_DIR`:
 
 ```shell
-mkdir ~/xos
-cd ~/xos
+mkdir $SRC_DIR/
+cd $SRC_DIR
 repo init -u https://gerrit.opencord.org/xos-manifest -b master
 repo sync
 ```
 
-When this is complete, a listing (`ls`) inside this directory should yield
-output similar to:
-
-```shell
-./				helm-charts/			xos-rest-gw/
-../				profiles/			xos-sample-gui-extension/
-.repo/					services/			xos-tosca/
-automation-tools/		xos-core/
-components/			xos-gui/
-```
-
 ## Development Notes
 
 You can also use `repo` to download the latest patchsets from Gerrit, and
diff --git a/docs/tutorials/basic_synchronizer.md b/docs/tutorials/basic_synchronizer.md
index 778621f..bd8ed5d 100644
--- a/docs/tutorials/basic_synchronizer.md
+++ b/docs/tutorials/basic_synchronizer.md
@@ -14,7 +14,7 @@
 ## Prerequisites
 
 The following assumes you start with a simple deployment of
-XOS on `minikube` as described [here](../install.md), so that
+XOS on Kubernetes, so that
 running `kubectl get pods` returns something similar to:
 
 ```shell
@@ -28,24 +28,24 @@
 xos-ws-748c7f9f75-cnjnh          1/1       Running   0          21h
 ```
 
-The tutorial also assumes you have downloaded the XOS source code,
-as described [here](../repo.md).
+The tutorial also assumes you have downloaded the XOS source code
+into directory `$SRC_DIR`.
 
 ## Directory Structure
 
-XOS services are located under `~/xos/services`. The first step
+XOS services are located under `$SRC_DIR/services`. The first step
 is to create a new directory to store our models and synchronizer
 code. We will use the name `hello-world` for this example:
 
 ```shell
-cd ~/xos/services
+cd $SRC_DIR/services
 mkdir hello-world
 cd hello-world
 ```
 
 Although empty when we start, we will end up with a directory
 structure that looks like the following. You can look at the
-corresponding directories of other services in `~/xos/services`
+corresponding directories of other services in `$SRC_DIR/services`
 for examples.
 
 ```shell
@@ -136,8 +136,9 @@
       level: DEBUG
 ```
 
-This tells the synchronizer framework in a running system where
-to fine the configuration parameters specific to HelloWorld.
+This tells the synchronizer framework in a running container where
+to fine the configuration parameters specific to HelloWorld. By
+convention, we use `/opt/xos`.
 
 ## Define Models
 
@@ -169,7 +170,7 @@
 `Service` model, and `HelloWorldServiceInstance` extends the
 `ServiceInstance` model. Both of these models inherit the
 attributes defined in the parent classes, which you can see in
-file `~/xos/xos-core/core/models/core.xproto`.
+file `$SRC_DIR/xos-core/core/models/core.xproto`.
 
 ## Load the Models into the Core
 
@@ -218,7 +219,7 @@
 ```
 
 Now we can build our synchronizer image by executing the following
-from the `~/xos/service/hello-world` directory:
+from the `$SRC_DIR/service/hello-world` directory:
 
 ```shell
 eval $(minikube docker-env)