Add test-coverage & codecov target and update circleci

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

Makefile

@@ -14,6 +14,19 @@ clean:
 test:
 	go test -tags daemon -v $(shell go list ./... | grep -v /vendor/)
 
+.PHONY: test-coverage
+test-coverage:
+	for pkg in $(shell go list ./... | grep -v /vendor/); do \
+		go test -tags daemon -v -cover -parallel 8 -coverprofile=profile.out -covermode=atomic $${pkg} || exit 1; \
+		if test -f profile.out; then \
+			cat profile.out >> coverage.txt && rm profile.out; \
+		fi; \
+	done
+
+.PHONY: codecov
+codecov:
+	$(shell curl -s https://codecov.io/bash | bash)
+
 .PHONY: lint
 lint:
 	gometalinter --config gometalinter.json ./...