VOL-2629 Modified Makefile to use containerized tools.

Modified existing containers to build internally, rather than bind-mounting the whole project & running make targets.
This repo has C dependencies, which must be made available, which complicates the usage of containerized tools.  Some tool containers are augmented before use.
"build-" targets will continue to use locally installed golang.
"release-" targets will use containerized tools, and will cross-compile only bbsimctl.

Change-Id: I02c999a29361d26aa9198d1f03b2b050febfe954
diff --git a/tools/main.go b/tools/main.go
index b387490..4d093a2 100644
--- a/tools/main.go
+++ b/tools/main.go
@@ -13,14 +13,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 // +build tools
 
 package tools
 
 import (
 	// protocol buffer compiler plugins
-	_ "github.com/golang/protobuf/protoc-gen-go"
-	_ "github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway"
-	_ "github.com/grpc-ecosystem/grpc-gateway/protoc-gen-swagger"
+	_ "github.com/grpc-ecosystem/grpc-gateway/protoc-gen-swagger/options"
 )