VOL-4840 - Tracking ticket for release documentation.

conf.py
-------
  o Define more external link macros to shorten URLs.

Misc
----
  o Updated comments on version strings and misc items.

Change-Id: Ib4bc650e575bdc4b5c6a666c4147c8b93a41e797
diff --git a/makefiles/virtualenv.mk b/makefiles/virtualenv.mk
index faa7c60..e8cab77 100644
--- a/makefiles/virtualenv.mk
+++ b/makefiles/virtualenv.mk
@@ -20,13 +20,13 @@
 
 vst_venv-2 : vst_venv/bin/activate requirements.txt
 
-vst_venv/bin/activate:
-	virtualenv -p python3 $@ ;\
-	source ./$@/bin/activate ;\
-	python -m pip install -r requirements.txt
+vst_venv/bin/activate: requirements.txt
+	virtualenv -p python3 $@
 
-zzz: xyz
-xyz: vst_venv/bin/activate
-	source vst_venv/bin/activate
+	@echo	
+	@[ -r requirements.txt ]\
+  && { echo "python -m pip install -r requirements.txt"; }\
+  && source ./$@/bin/activate\
+  && python -m pip install -r requirements.txt
 
 # [EOF]