Makefile improvements

.gitignore
----------
  o Added .venv/ so git will ignore local python virtual env.

Makefile
--------
  o Update copyright notice to latest syntax (w/SPDX tokens).
  o Remove dup go-protos and java-protos as build target dependencies,
    build depends on protos which depends on {build,go}-protos.
  o Changed "python ./setup.py sdist" to "$(activate) && python ...",
    difference: cmd[1] is system interpreter, cmd[2] is installed
    virtualenv interpreter used by all other commands.

makefiles/help/include.mk
makefiles/help/go.mk
makefiles/help/java.mk
makefiles/help/python.mk
------------------------
  o Help target formatting and cleanup.
  o Not all language targets {go,java,python}-* were documented.

Change-Id: I752ec3f38ae28f868934f36460e5fd3f588bd810
Signed-off-by: Eric Ball <eball@linuxfoundation.org>
diff --git a/makefiles/help/go.mk b/makefiles/help/go.mk
index 9ec36db..57d2b0a 100644
--- a/makefiles/help/go.mk
+++ b/makefiles/help/go.mk
@@ -16,10 +16,9 @@
 # -----------------------------------------------------------------------
 
 help ::
-	@echo
-	@echo '[GO]'
-	@echo '  go-all      Build & test all go targets'
-	@echo '  go-protos'
-	@echo '  go-test'
+	@printf '\n[LANGUAGE: go]\n'
+	@printf '  %-33.33s %s\n' 'go-all'    'Build & test all go targets'
+	@printf '  %-33.33s %s\n' 'go-protos' 'Generate go prototypes'
+	@printf '  %-33.33s %s\n' 'go-test'   'Validate generated prototypes'
 
 # [EOF]