Upgrade golang to v1.13.1 (quii#258)

.travis.yml

@@ -1,9 +1,8 @@
-sudo: required
+dist: bionic
 language: go
 
 go:
-  - 1.10.x
-  - 1.11.x
+  - 1.13.x
 
 before_install:
   - go get github.com/quii/learn-go-with-tests/command-line/v1

go.mod

@@ -1,8 +1,5 @@
 module github.com/quii/learn-go-with-tests
 
-go 1.12
+go 1.13
 
-require (
-	github.com/client9/misspell v0.3.4 // indirect
-	github.com/gorilla/websocket v1.4.1
-)
+require github.com/gorilla/websocket v1.4.1

go.sum

@@ -1,6 +1,2 @@
-github.com/client9/misspell v0.3.4 h1:ta993UF76GwbvJcIo3Y68y/M3WxlpEHPWIGDkJYwzJI=
-github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
-github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q=
-github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvKCM=
 github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=

install-go.md

@@ -32,7 +32,7 @@ You can verify the installation with:
 
 ```sh
 $ go version
-go version go1.10 darwin/amd64
+go version go1.13.1 darwin/amd64
 ```
 
 ## Go Environment