Make must test Go by default, not rebuild world.

``lib/go/Makefile.am`` made erroneous assumptions that it should
forcibly rebuild all of thrift4go dependencies.  This seemed like a
good idea at the time for sanity checking reasons, but it requires
in reality extra permissions, which the user building thrift4go may
not have.

The same rationale applies for why the make rules ought to build and
test Go instead of installing them by default.

lib/go/Makefile.am

@@ -17,33 +17,34 @@
 # under the License.
 #
 
-# N.B.(matttproud): The flag assumptions of this makefile could be improved to
-#                   potentially be more cross-platform compatible.  For
-#                   instance, I think the »-t« flag for »cp« may be invalid on
-#                   BSD and Darwin systems.
-
-all: install
-
+all: test
 
 export GOPATH = $(PWD)
 SOURCE = $(GOPATH)/{pkg,src}
 DESTINATION = $(DESTDIR)/$(GOROOT)
 
-
 clean-local:
 	go clean thrift
 
 nuke-local:
 	go clean -i -r -x thrift
 	$(RM) -rf bin pkg
 
+# N.B.(matttproud): This step may fail to run with sudo due to sudo clearing
+#                   environment variables before changing permissions for
+#                   security reasons.  This can be avoided by using the
+#                   DESTDIR construct described above to provide emissions to
+#                   an intermediate directory for subsequent manual merging.
+
 install-exec-local: test
-	go install -a -v -x thrift
-	mkdir -vp "$(DESTINATION)"
-	cp -av $(SOURCE) -t "$(DESTINATION)"
+	go install -v -x thrift
+	install -d "$(GOPATH)/pkg"
+	install -d "$(GOPATH)/src"
+	cp -av "$(GOPATH)/pkg/" "$(DESTINATION)/pkg/"
+	cp -av "$(GOPATH)/src/" "$(DESTINATION)/src/"
 
 test: check
-	go test -a -v -x thrift
+	go test -v -x thrift
 
 check-local:
-	go build -a -v -x thrift
+	go build -v -x thrift