Have you read this "callback contain no result Error: Error: base fee exceeds gas limit" when call selfdestruct function (using Remix IDE) ?
I suggest to test your contract using MyEtherwalletMyEtherWallet. The setup is quite simple:
- visit https://www.myetherwallet.com/
- on the top-right corner, select the dropdown menu and choose "Add Custom Node"
- add the IP address and port number where testrpc is running (tipically is http://127.0.0.1:8545)
- go to contract tab and insert the contract address (deployed with Remix) and its ABI interface
Now you can interact with your contract.
In your example, I called the witdraw() function with gas limit 30000 and it works.