Add Circle ci (#41)

* fix compile errors.

* fix lint errors.

* add circle-ci job.

* rename IDHigh to TraceIDHigh

* rename the file.

* add go get for goimports and golangci-lint

* enable GO111MODULE and remove comments.

* remove working dir and update cache name

* Add TEST_RESULT env back.

* run go mod tidy.

* remove go mod download.

* add test coverage.

* fix TraceID.

* fix circlefi config error.

* remove install-tools.

* remove ALL_TEST_SRC from Makefile.

Makefile

@@ -1,3 +1,12 @@
+ALL_SRC := $(shell find . -name '*.go' -type f | sort)
+ALL_PKGS := $(shell go list $(sort $(dir $(ALL_SRC))))
+
+GOTEST=go test
+GOTEST_OPT?=-v -race -timeout 30s
+GOTEST_OPT_WITH_COVERAGE = $(GOTEST_OPT) -coverprofile=coverage.txt -covermode=atomic
+
+.DEFAULT_GOAL := precommit
+
 .PHONY: precommit
 
 TOOLS_DIR := ./.tools
@@ -10,4 +19,26 @@ $(TOOLS_DIR)/goimports: go.mod go.sum tools.go
 
 precommit: $(TOOLS_DIR)/goimports $(TOOLS_DIR)/golangci-lint 
 	$(TOOLS_DIR)/goimports -d -local github.com/open-telemetry/opentelemetry-go -w .
-	$(TOOLS_DIR)/golangci-lint run
+	$(TOOLS_DIR)/golangci-lint run # TODO: Fix this on windows.
+
+.PHONY: test-with-coverage
+test-with-coverage:
+	$(GOTEST) $(GOTEST_OPT_WITH_COVERAGE) $(ALL_PKGS)
+	go tool cover -html=coverage.txt -o coverage.html
+
+.PHONY: circle-ci
+circle-ci: precommit test-with-coverage test-386
+
+.PHONY: test
+test:
+	$(GOTEST) $(GOTEST_OPT) $(ALL_PKGS)
+
+.PHONY: test-386
+test-386:
+	GOARCH=386 $(GOTEST) -v -timeout 30s $(ALL_PKGS)
+
+all-pkgs:
+	@echo $(ALL_PKGS) | tr ' ' '\n' | sort
+
+all-srcs:
+	@echo $(ALL_SRC) | tr ' ' '\n' | sort