Problem: no CI configuration

Solution: add Travis CI configuration

Refs gosh-lang#15.

.codecov.yml

@@ -0,0 +1,2 @@
+coverage:
+  range: "75...85"

.travis.yml

@@ -0,0 +1,28 @@
+dist: trusty
+language: go
+
+go:
+  - 1.11.x
+  - master
+
+env:
+  - GO111MODULE=off
+  - GO111MODULE=on
+
+go_import_path: gosh-lang.org/gosh
+
+install:
+  - make init
+
+script:
+  - make test
+
+  # golangci-lint does not work with modules yet
+  # https://github.com/golangci/golangci-lint/issues/178
+  - if [ "$GO111MODULE" = "on" ]; then
+      go mod vendor -v;
+    fi
+  - env GO111MODULE=off make check;
+
+after_success:
+  - bash <(curl -s https://codecov.io/bash) -f cover.out -X fix -e GO111MODULE

Makefile

@@ -1,15 +1,17 @@
 all: test
 
 init:
-	go get -u golang.org/x/tools/cmd/stringer \
-				github.com/dvyukov/go-fuzz/... \
-				github.com/golangci/golangci-lint/cmd/golangci-lint
+	go get -u -v golang.org/x/tools/cmd/stringer \
+					github.com/dvyukov/go-fuzz/go-fuzz-build \
+					github.com/dvyukov/go-fuzz/go-fuzz \
+					github.com/golangci/golangci-lint/cmd/golangci-lint
 
-	go test -i -v ./...
+	go get -t -v ./...
 
 install:
 	go generate ./...
 	go install -v ./...
+	go test -i -v ./...
 
 test: install
 	go build -v -tags gofuzz ./...

README.md

@@ -1,5 +1,7 @@
 # Gosh
 
+[![Travis CI Build Status](https://travis-ci.org/gosh-lang/gosh.svg)](https://travis-ci.org/gosh-lang/gosh)
+
 Gosh is an interpreted language for Go ecosystem written in Go.
 
 It is in super-early pre-alpha stage. It is also an experiment in community building.