Make it work with Go 1.5

Author: x1ddos

Makefile

@@ -1,6 +1,6 @@
 SHA := $(shell git rev-parse --short HEAD)
 DATE := $(shell TZ=UTC date +%FT%T)Z
-VERSION := "$(shell cat VERSION) $(DATE) $(SHA)"
+VERSION := $(shell cat VERSION)-$(DATE)-$(SHA)
 
 RELEASES=release/imgdiff-darwin-amd64 \
 	 release/imgdiff-darwin-386 \
@@ -10,7 +10,7 @@ RELEASES=release/imgdiff-darwin-amd64 \
 	 release/imgdiff-windows-386.exe
 
 SRCS=./cmd/imgdiff/*.go
-LDFLAGS=-ldflags '-X main.version $(VERSION)'
+LDFLAGS=-ldflags "-X main.version=$(VERSION)"
 
 imgdiff: $(SRCS)
 	go build -o imgdiff $(LDFLAGS) $(SRCS)
@@ -28,27 +28,21 @@ deps:
 release: $(RELEASES)
 
 release/imgdiff-darwin-amd64: $(SRCS)
-	cd $(GOROOT)/src && GOOS=darwin GOARCH=amd64 ./make.bash
 	GOOS=darwin GOARCH=amd64 go build -o $@ $(LDFLAGS) $(SRCS)
 
 release/imgdiff-darwin-386: $(SRCS)
-	cd $(GOROOT)/src && GOOS=darwin GOARCH=386 ./make.bash
 	GOOS=darwin GOARCH=386 go build -o $@ $(LDFLAGS) $(SRCS)
 
 release/imgdiff-linux-amd64: $(SRCS)
-	cd $(GOROOT)/src && GOOS=linux GOARCH=amd64 ./make.bash
 	GOOS=linux GOARCH=amd64 go build -o $@ $(LDFLAGS) $(SRCS)
 
 release/imgdiff-linux-386: $(SRCS)
-	cd $(GOROOT)/src && GOOS=linux GOARCH=386 ./make.bash
 	GOOS=linux GOARCH=386 go build -o $@ $(LDFLAGS) $(SRCS)
 
 release/imgdiff-windows-amd64.exe: $(SRCS)
-	cd $(GOROOT)/src && GOOS=windows GOARCH=amd64 ./make.bash
 	GOOS=windows GOARCH=amd64 go build -o $@ $(LDFLAGS) $(SRCS)
 
 release/imgdiff-windows-386.exe: $(SRCS)
-	cd $(GOROOT)/src && GOOS=windows GOARCH=386 ./make.bash
 	GOOS=windows GOARCH=386 go build -o $@ $(LDFLAGS) $(SRCS)
 
 clean: