Add basic interactive overwrite strategy

Available options:

- Do not copy
- Overwrite dest
- Copy source as dest.dist

internal/project/git.go

@@ -1,7 +1,7 @@
 package project
 
 import (
-	"log"
+	"fmt"
 	"net/url"
 	"os"
 	"strings"
@@ -51,7 +51,7 @@ func (f *GitFetcher) Fetch(url *url.URL) (billy.Filesystem, error) {
 		url.Fragment = ""
 	}
 
-	log.Printf("Cloning repository '%s'...", url.String())
+	fmt.Printf("Cloning repository '%s'.\n", url.String())
 
 	repo, err := git.Clone(memory.NewStorage(), fs, &git.CloneOptions{
 		URL:           url.String(),
@@ -72,7 +72,7 @@ func (f *GitFetcher) Fetch(url *url.URL) (billy.Filesystem, error) {
 		return nil, errors.Wrap(err, "could not retrieve worktree")
 	}
 
-	log.Printf("Checking out branch '%s'...", branchName)
+	fmt.Printf("Checking out branch '%s'.\n", branchName)
 
 	err = worktree.Checkout(&git.CheckoutOptions{
 		Force:  true,