Generates invalid code when given more than 1 statement (without -quiet).

[dmitshur]

It works okay when given a single statement and -quiet is not used:

$ goexec -n 'fmt.Println("hi")'
package main

import (
	"fmt"

	"github.com/shurcooL/go-goon"
)

func main() {
	goon.Dump(fmt.Println("hi"))
}

But it generates invalid code when given multiple statements and -quiet is not used:

$ goexec -n 's := "hi"; fmt.Println(s)'
package main

import (
	"github.com/shurcooL/go-goon"
)

func main() {
	goon.Dump(s := "hi"; fmt.Println(s))
}
imports.Process: gen.go:8:14: missing ',' in argument list

It should've been turned into:

s := "hi"; goon.Dump(fmt.Println(s))

A fix might be to parse the input, count number of statements, and add goon.Dump around the last one only.

Need to parse as Go code. Otherwise it could fail on input that contains a string with a semicolon, e.g., goexec 'fmt.Println("foo;bar")'.