Replace home directory before performing SaveAs

Fixes #820

cmd/micro/buffer.go

@@ -409,9 +409,9 @@ func (b *Buffer) SaveAs(filename string) error {
 	}
 	str := b.SaveString(b.Settings["fileformat"] == "dos")
 	data := []byte(str)
-	err := ioutil.WriteFile(filename, data, 0644)
+	err := ioutil.WriteFile(ReplaceHome(filename), data, 0644)
 	if err == nil {
-		b.Path = ReplaceHome(filename)
+		b.Path = filename
 		b.IsModified = false
 		b.ModTime, _ = GetModTime(filename)
 		return b.Serialize()