Add ERC1155 support

[axvn]

Description

Added ERC1155 support, this is built on the ERC20 data format 0x[tokenId][amount][addressLen][address], rather than using the batchMint data format proposed by the ERC1155Handler, corresponding changes needed in the ChainBridge-solidity repository.

Related Issue Or Context

Changed ERC1155Handler to use the simpler mint function.

ChainSafe/chainbridge-solidity#516

How Has This Been Tested? Testing details.

UnitTest provided, including go wrappers to the new handler.

Live demo can be tried out here: http://13.250.39.184:3001 (bridge between Mumbai and Rinkeby), you can get test tokens from opensea testnet.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation

Checklist:

• I have commented my code, particularly in hard-to-understand areas.
• I have ensured that all acceptance criteria (or expected behavior) from issue are met
• I have updated the documentation locally and in chainbridge-docs.
• I have added tests to cover my changes.
• I have ensured that all the checks are passing and green, I've signed the CLA bot

[CLAassistant]

All committers have signed the CLA.

[mpetrun5]

Thanks a lot for the contribution!

In general looks good to me I would just like to see an an integration test here:

chainbridge-core/e2e/evm/test.go

Line 132 in 1c368e6

func (s *IntegrationTestSuite) TestErc721Deposit() {

[mpetrun5]

I would wait until the solidity team approves the solidity changes first before merging this.