Add a "make test-cmd" target

This is a convenience function to allow a user to generate a
"go test" command string with the requisite build-specific
parameters already filled in.  It does not run any code.  It
is only for allowing the user to forumlate their own go-test
session (typically in conjunction with running a specific
pkg/test or under a debugger).

Change-Id: I3bfe9bfcaf136159b4a447a76a641b6ab0c54ce6
Signed-off-by: Greg Haskins <gregory.haskins@gmail.com>

Makefile

@@ -21,6 +21,7 @@
 #   - peer - builds a native fabric peer binary
 #   - orderer - builds a native fabric orderer binary
 #   - unit-test - runs the go-test based unit tests
+#   - test-cmd - generates a "go test" string suitable for manual customization
 #   - behave - runs the behave test
 #   - behave-deps - ensures pre-requisites are availble for running behave manually
 #   - gotools - installs go tools like golint
@@ -118,6 +119,10 @@ unit-test: peer-docker testenv couchdb
 
 unit-tests: unit-test
 
+# Generates a string to the terminal suitable for manual augmentation / re-issue, useful for running tests by hand
+test-cmd:
+	@echo "go test -ldflags \"$(GO_LDFLAGS)\""
+
 docker: $(patsubst %,build/image/%/$(DUMMY), $(IMAGES))
 native: peer orderer