Remove unused Makefile.

Plugin/Makefile

@@ -1,21 +0,0 @@
-
-default:	build
-
-build:  clear
-	swift build 
-	cp .build/debug/protoc-gen-swiftgrpc .
-	cp .build/debug/protoc-gen-swift .
-
-test:	build
-	protoc ../Examples/Echo/echo.proto --proto_path=../Examples/Echo --plugin=./protoc-gen-swiftgrpc --swiftgrpc_out=. --swift_out=. --swiftgrpc_opt=TestStubs=true
-	diff echo.grpc.swift ../Examples/Echo/Generated/echo.grpc.swift
-
-deploy:
-	cp echo.grpc.swift ../Examples/Echo/Generated/echo.grpc.swift 
-
-clear : 
-	rm -f *.pb.swift *.grpc.swift
-
-clean : clear
-	rm -rf protoc-gen-swiftgrpc Packages .build protoc-gen-swift Package.pins
-	rm -rf Package.resolved