Added v1->v2 migration into CI

Also fixed issue where migration would not handle large dirs due to v1
iteration changing the pair of the directory.

.travis.yml

@@ -130,7 +130,58 @@ jobs:
         - ls -flh
         - make -B test_dirs test_files QUIET=1
 
-      # Automatically update releases
+    # self-host with littlefs-fuse for fuzz test
+    - stage: test
+      env:
+        - STAGE=test
+        - NAME=littlefs-migration
+      install:
+        - sudo apt-get install libfuse-dev
+        - git clone --depth 1 https://github.com/geky/littlefs-fuse -b v2-alpha v2
+        - git clone --depth 1 https://github.com/geky/littlefs-fuse v1
+        - fusermount -V
+        - gcc --version
+      before_script:
+        # setup disk for littlefs-fuse
+        - rm -rf v2/littlefs/*
+        - cp -r $(git ls-tree --name-only HEAD) v2/littlefs
+
+        - mkdir mount
+        - sudo chmod a+rw /dev/loop0
+        - dd if=/dev/zero bs=512 count=4096 of=disk
+        - losetup /dev/loop0 disk
+      script:
+        # compile v1 and v2
+        - make -C v1
+        - make -C v2
+
+        # run self-host test with v1
+        - v1/lfs --format /dev/loop0
+        - v1/lfs /dev/loop0 mount
+
+        - ls mount
+        - mkdir mount/littlefs
+        - cp -r $(git ls-tree --name-only HEAD) mount/littlefs
+        - cd mount/littlefs
+        - stat .
+        - ls -flh
+        - make -B test_dirs test_files QUIET=1
+
+        # attempt to migrate
+        - cd ../..
+        - fusermount -u mount
+
+        - v2/lfs --migrate /dev/loop0
+        - v2/lfs /dev/loop0 mount
+
+        # run self-host test with v2 right where we left off
+        - ls mount
+        - cd mount/littlefs
+        - stat .
+        - ls -flh
+        - make -B test_dirs test_files QUIET=1
+
+    # Automatically create releases
     - stage: deploy
       env:
         - STAGE=deploy