Commit logspout binary to repository; update Dockerfile reference and Makefile

Updated Makefile:
 - to have a stage/logspout target which copies the build output to the stage directory
 - to depend upon the stage/logspout when building the container
 - to force the OS/ARCH to be linux/amd64 (prevent Mac users from destroying the world)

Updated Dockerfile:
 - ADDs from the stage location

Author: BiggerNoise

Dockerfile

@@ -1,7 +1,7 @@
 FROM flynn/busybox
 MAINTAINER Jeff Lindsay <progrium@gmail.com>
 
-ADD ./build/logspout /bin/logspout
+ADD ./stage/logspout /bin/logspout
 
 ENV DOCKER unix:///tmp/docker.sock
 ENV ROUTESPATH /mnt/routes

Makefile

@@ -1,9 +1,13 @@
-build/container: build/logspout Dockerfile
+build/container: stage/logspout Dockerfile
 	docker build --no-cache -t logspout .
 	touch build/container
 
 build/logspout: *.go
-	go build -o build/logspout
+	GOOS=linux GOARCH=amd64 go build -o build/logspout
+
+stage/logspout: build/logspout
+	mkdir -p stage
+	cp build/logspout stage/logspout
 
 release:
 	docker tag logspout progrium/logspout