travis: install libfuse for cmount build and disable on OS X

.travis.yml

@@ -18,12 +18,18 @@ script:
 env:
   matrix:
     secure: gU8gCV9R8Kv/Gn0SmCP37edpfIbPoSvsub48GK7qxJdTU628H0KOMiZW/T0gtV5d67XJZ4eKnhJYlxwwxgSgfejO32Rh5GlYEKT/FuVoH0BD72dM1GDFLSrUiUYOdoHvf/BKIFA3dJFT4lk2ASy4Zh7SEoXHG6goBlqUpYx8hVA=
+addons:
+  apt:
+    packages:
+    - fuse
+    - libfuse-dev
 matrix:
   allow_failures:
   - go: tip
   include:
   - os: osx
     go: 1.8.1
+    env: CGO_ENABLED=0
 deploy:
   provider: script
   script: make travis_beta

Makefile

@@ -34,7 +34,7 @@ test:	rclone
 # Quick test
 quicktest:
 	RCLONE_CONFIG="/notfound" go test $(GO_FILES)
-	RCLONE_CONFIG="/notfound" go test -cpu=2 -race $(GO_FILES)
+	if [ "$$CGO_ENABLED" != "0" ]; then RCLONE_CONFIG="/notfound" go test -cpu=2 -race $(GO_FILES) ; fi
 
 # Do source code quality checks
 check:	rclone