Remove unnecessary homedir module (#88)

`os.UserHomeDir` is supported in go1.12+. We no longer need a third party module to load the home directory.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

cmd/ack-generate/command/root.go

@@ -18,7 +18,6 @@ import (
 	"os"
 	"path/filepath"
 
-	"github.com/mitchellh/go-homedir"
 	"github.com/spf13/cobra"
 )
 
@@ -62,7 +61,7 @@ func init() {
 		os.Exit(1)
 	}
 
-	hd, err := homedir.Dir()
+	hd, err := os.UserHomeDir()
 	if err != nil {
 		fmt.Printf("unable to determine $HOME: %s\n", err)
 		os.Exit(1)

go.mod

@@ -10,7 +10,6 @@ require (
 	github.com/gertd/go-pluralize v0.1.1
 	github.com/ghodss/yaml v1.0.0
 	github.com/iancoleman/strcase v0.1.3
-	github.com/mitchellh/go-homedir v1.1.0
 	github.com/operator-framework/api v0.6.0
 	github.com/pkg/errors v0.9.1
 	github.com/spf13/cobra v1.1.1

scripts/build-controller.sh

@@ -19,7 +19,7 @@ if ! k8s_controller_gen_version_equals "$CONTROLLER_TOOLS_VERSION"; then
     exit 1
 fi
 
-ACK_GENERATE_CACHE_DIR=${ACK_GENERATE_CACHE_DIR:-"~/.cache/aws-controllers-k8s"}
+ACK_GENERATE_CACHE_DIR=${ACK_GENERATE_CACHE_DIR:-"$HOME/.cache/aws-controllers-k8s"}
 # The ack-generate code generator is in a separate source code repository,
 # typically at $GOPATH/src/github.com/aws-controllers-k8s/code-generator
 DEFAULT_ACK_GENERATE_BIN_PATH="$ROOT_DIR/bin/ack-generate"