add Prompt and PromptPassword

Author: Mario L Gutierrez

README.md

@@ -226,6 +226,20 @@ Inside("somedir", func() {
 })
 ```
 
+## User Input
+
+To get plain string
+
+```go
+user := Prompt("user: ")
+```
+
+To get password
+
+```go
+password := PromptPassword("password: ")
+```
+
 ## Godofile Run-Time Environment
 
 To specify whether to inherit from parent's process environment,

exec.go

@@ -1,11 +1,14 @@
 package godo
 
 import (
+	"bufio"
+	"fmt"
 	"os"
 	"path"
 	"strconv"
 	"strings"
 
+	"github.com/howeyc/gopass"
 	"github.com/mgutz/str"
 )
 
@@ -161,3 +164,17 @@ func Inside(dir string, lambda func()) error {
 	lambda()
 	return nil
 }
+
+// Prompt prompts user for input with default value.
+func Prompt(prompt string) string {
+	reader := bufio.NewReader(os.Stdin)
+	fmt.Print(prompt)
+	text, _ := reader.ReadString('\n')
+	return text
+}
+
+// PromptPassword prompts user for password input.
+func PromptPassword(prompt string) string {
+	fmt.Printf(prompt)
+	return string(gopass.GetPasswd())
+}