[FAB-15104] Remove versions from fabric-samples readme

Remove versions from fabric-samples readme so that
it doesn't need to be maintained for each release.
Also clarify the bootstrap.sh download instructions.

Change-Id: I4ef80e048b0d8f27429059635e57e08a8c70c0fa
Signed-off-by: David Enyeart <enyeart@us.ibm.com>

README.md

@@ -9,20 +9,24 @@ intend to use to ensure alignment.
 
 ## Download Binaries and Docker Images
 
-The `scripts/bootstrap.sh` (available in the fabric repository)
-script will preload all of the requisite docker
-images for Hyperledger Fabric and tag them with the 'latest' tag. Optionally,
-specify a version for fabric, fabric-ca and thirdparty images. Default versions
-are 1.4.1, 1.4.1 and 0.4.15 respectively.
+The installation instructions will utilize `scripts/bootstrap.sh` (available in the fabric repository)
+script to download all of the requisite Hyperledger Fabric binaries and docker
+images, and tag the images with the 'latest' tag. Optionally,
+specify a version for fabric, fabric-ca and thirdparty images. If versions
+are not passed, the latest available versions will be downloaded.
 
+The script will also clone fabric-samples repository using the version tag that
+is aligned with the Fabric version.
+
+You can also download the script and execute locally:
 
 ```bash
 # Fetch bootstrap.sh from fabric repository using
 curl -sS https://raw.githubusercontent.com/hyperledger/fabric/master/scripts/bootstrap.sh -o ./scripts/bootstrap.sh
 # Change file mode to executable
 chmod +x ./scripts/bootstrap.sh
-# Download binaries and docker images (bypass fabric-samples repo clone)
-./scripts/bootstrap.sh [version] [ca version] [thirdparty_version] -s
+# Download binaries and docker images
+./scripts/bootstrap.sh [version] [ca version] [thirdparty_version]
 ```
 
 ### Continuous Integration