[EVM-706]: Provide native token initial total supply

[goran-ethernal]

Description

In 0xPolygon/edge-contracts@befb417, we added initial total supply when initializing native ERC20 tokens.

This PR adds that initial total supply parameter when initializing those tokens on start of child chain. Basically we run through the Alloc map in genesis, sum up all balances from all addresses (that are premined, except for the zero address since its a special case address), and initialize tokens with it.

This PR also added appropriate checks for this in the e2e tests.

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually

[Stefan-Ethernal]

LGTM, aside from minor nitpicks.