Convert for to do while to save gas on multiple runs

[Arkay92]

No description provided.

[cygaar]

Can you rebase and post the gas difference before and after?

[sennett-lau]

It seems the commit does not pass the test, the following should be changed
line 53: i > tokenIds.length to i >= tokenIds.length
line 64: i > tokenIds.length to i < tokenIds.length
line 77: i > chipAddressesOld.length to i >= chipAddressesOld.length
line 97: i >chipAddressesOld.length to i < chipAddressesOld.length

I combined this idea with my PR with a gas difference before and after here

[Arkay92]

[PASS] testGetTokenDataForChipSignature() (gas: 127921 -> 127892)
[PASS] testGetTokenDataForChipSignatureBlockNumTooOld() (gas: 122467 ->122438 )
[PASS] testGetTokenDataForChipSignatureInvalid() (gas: 131763 -> 131734)
[PASS] testGetTokenDataForChipSignatureInvalidBlockNumber() (gas: 122301 -> 122272)
[PASS] testIsChipSignatureForToken() (gas: 216704 -> 216675)
[PASS] testMintTokenWithChip() (gas: 176564 -> 176535)
[PASS] testSeedChipToTokenMapping() (gas: 115247 -> 115218)
[PASS] testSeedChipToTokenMappingExistingToken() (gas: 212294 -> 212240)
[PASS] testSeedChipToTokenMappingInvalidInput() (gas: 17178 -> 17178)
[PASS] testSupportsInterface() (gas: 7059 -> 7059)
[PASS] testTokenIdFor() (gas: 117084 -> 117056)
[PASS] testTokenIdMappedFor() (gas: 66778 -> 66750)
[PASS] testTransferTokenWithChip(bool) (runs: 256, μ: 211867, ~: 211785 -> runs: 256, μ: 211835, ~: 211756)
[PASS] testUpdateChips() (gas: 171052 -> 171002)
[PASS] testUpdateChipsInvalidInput() (gas: 16433 -> 16433)
[PASS] testUpdateChipsUnsetChip() (gas: 23430 -> 23405)

[Arkay92]

After adding laubs unchecked to do while cut gas down significantly #13

[PASS] testGetTokenDataForChipSignature() (gas: 127921 -> 127752)
[PASS] testGetTokenDataForChipSignatureBlockNumTooOld() (gas: 122467 -> 122298)
[PASS] testGetTokenDataForChipSignatureInvalid() (gas: 131763 -> 131594)
[PASS] testGetTokenDataForChipSignatureInvalidBlockNumber() (gas: 122301 -> 122132)
[PASS] testIsChipSignatureForToken() (gas: 216704 -> 216535)
[PASS] testMintTokenWithChip() (gas: 176564 -> 176395)
[PASS] testSeedChipToTokenMapping() (gas: 115247 -> 115078)
[PASS] testSeedChipToTokenMappingExistingToken() (gas: 212100-> 212100)
[PASS] testSupportsInterface() (gas: 7059 -> 7059)
[PASS] testTokenIdFor() (gas: 117084 -> 116986)
[PASS] testTokenIdMappedFor() (gas: 66778 -> 66680)
[PASS] testTransferTokenWithChip(bool) (runs: 256, μ: 211881, ~: 211785 -> runs: 256, μ: 211706, ~: 211616)
[PASS] testUpdateChips() (gas: 171052 -> 170776)
[PASS] testUpdateChipsInvalidInput() (gas: 16433 -> 16433)
[PASS] testUpdateChipsUnsetChip() (gas: 23430 -> 23405)