Add ability to build s3-plugin into ipfs-10-to-11 migration

This addresses issue #122.

- Use Makefile for each migration to build and cleanup
- Update README.md to describe building with plugin

Makefile

@@ -2,7 +2,9 @@ GO111MODULE = on
 
 MIG_DIRS = $(shell ls -d ipfs-*-to-*)
 
-.PHONY: build clean cmd sharness test test_go
+.PHONY: all build clean cmd sharness test test_go
+
+all: build
 
 show: $(MIG_DIRS)
 	@echo "$(MIG_DIRS)"
@@ -12,7 +14,7 @@ build: $(shell ls -d ipfs-*-to-* | sed -e 's/ipfs/build.ipfs/') cmd
 
 build.%: MIGRATION=$*
 build.%:
-	cd $(MIGRATION) && go build -mod=vendor
+	make -C $(MIGRATION)
 
 cmd: cmd/fs-repo-migrations/fs-repo-migrations
 
@@ -31,7 +33,7 @@ clean: $(shell ls -d ipfs-*-to-* | sed -e 's/ipfs/clean.ipfs/')
 
 clean.%: MIGRATION=$*
 clean.%:
-	cd $(MIGRATION) && go clean
+	make -C $(MIGRATION) clean
 
 test_go: $(shell ls -d ipfs-*-to-* | sed -e 's/ipfs/test_go.ipfs/')
 	@echo OK

README.md

@@ -16,6 +16,7 @@ These are migrations for the filesystem repository of [ipfs](https://github.com/
   - [When should I migrate](#when-should-i-migrate)
   - [How to Run Migrations](#how-to-run-migrations)
   - [Developing Migrations](#developing-migrations)
+  - [Building with Plugin](#building-with-plugin)
 - [Contribute](#contribute)
   - [Want to hack on IPFS?](#want-to-hack-on-ipfs)
 - [License](#license)
@@ -71,6 +72,14 @@ If the migration directory contains a subdirectory named `sharness`, tests conta
 
 Dependencies must be vendored independently for each migration. Each migration is a separate go module with its own `vendor` directory (created with `go mod vendor` for that migration).  All migrations are built using `go build -mod=vendor` to ensure dependencies come from the module's `vendor` directory.
 
+
+### Building with Plugin
+Migrations starting with ipfs-10-to-11 can be built with plugins.  This is done by building the migration separately, using the appropriate make target.  For example, to build the ipfs-10-to-11 migtation with the s3 plugin:
+```
+cd ipfs-10-to-11
+make s3plugin
+```
+
 ## Contribute
 
 Feel free to join in. All welcome. Open an [issue](https://github.com/ipfs/fs-repo-migrations/issues)!

ipfs-0-to-1/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-1-to-2/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-10-to-11/Makefile

@@ -0,0 +1,30 @@
+TMPDIR = /tmp/tmp.fs-repo-migration_build
+TMP_GOIPFS = $(TMPDIR)/go-ipfs
+BIN = ipfs-10-to-11
+
+.PHONY: build clean s3plugin s3goipfs
+
+all: build
+
+build:
+	go build -mod=vendor
+
+s3goipfs:
+	rm -rf "$(TMPDIR)"
+	mkdir -p "$(TMPDIR)"
+	#git clone -b release-v0.8.0 https://github.com/ipfs/go-ipfs "$(TMP_GOIPFS)"
+	git clone https://github.com/ipfs/go-ipfs "$(TMP_GOIPFS)"
+	cd "$(TMP_GOIPFS)" && git checkout 852dfab997f58d9c36765c2fae7e619390f44fdb
+	cd "$(TMP_GOIPFS)" && go get github.com/ipfs/go-ds-s3@latest
+	echo "s3ds github.com/ipfs/go-ds-s3/plugin 0" >> $(TMP_GOIPFS)/plugin/loader/preload_list
+	make -C $(TMP_GOIPFS) build
+	go mod edit -replace  github.com/ipfs/go-ipfs=/tmp/tmp.fs-repo-migration_build/go-ipfs
+	go mod vendor
+
+s3plugin: s3goipfs build
+	@echo "===> Build with S3 plugin"
+
+clean:
+	go clean
+	rm -rf "$(TMPDIR)" vendor
+	git checkout vendor go.mod go.sum

ipfs-2-to-3/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-3-to-4/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-4-to-5/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-5-to-6/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-6-to-7/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-7-to-8/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-8-to-9/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean

ipfs-9-to-10/Makefile

@@ -0,0 +1,9 @@
+.PHONY: build clean
+
+all: build
+
+build:
+	go build -mod=vendor
+
+clean:
+	go clean