bugfix: balances::transfer for new_account

issue:#722
would_create flag should depend on dest, not origin.
change 
```rust
let would_create = from_balance.is_zero();
```
to 
```rust
    let to_balance = Self::free_balance(&dest); 
    let would_create = to_balance.is_zero(); 
```
in the other hand, provide `fn new_test_ext2()` and let `transfer_fee=10`, `creation_fee=50` for test case