Added sharness tests of cli tool

Pulling from the multihash sharness repository to run tests of the cli tool.
Forgot cache dir

Author: tabrath

.travis.yml

@@ -14,6 +14,7 @@ before_install:
 script:
   - go vet
   - go test -race -coverprofile=coverage.txt -covermode=atomic
+  - make sharness
 
 after_success:
     - bash <(curl -s https://codecov.io/bash)

Makefile

@@ -6,6 +6,11 @@ deps: gx
 	gx --verbose install --global
 	gx-go rewrite
 
+sharness: deps
+	git clone https://github.com/multiformats/multihash.git $(PWD)/sharness
+	cd $(PWD)/multihash && go build -v . && ls && chmod +x ./multihash
+	export MULTIHASH_BIN="$(PWD)/multihash/multihash" && export TEST_EXPENSE=1 && make -j1 -C $(PWD)/sharness/tests/sharness
+
 publish:
 	gx-go rewrite --undo