Arbitrum Nitro Contracts v1.0.3-beta.2

What's Changed

• Store rollup node ArbSys block numbers if on an Arbitrum host chain by @PlasmaPower in #6
• Document that gasEstimateL1Component doesn't pad its estimate by @PlasmaPower in #4
• Fix ABI encoding in sendWithdrawEthToFork by @PlasmaPower in #9
• Add a CI step to check the PR's base branch by @PlasmaPower in #7
• add serialized chain config to init message data by @magicxyyz in #8
• Changes from the nitro repo contracts-develop branch by @PlasmaPower in #3
• add getBlockDifficulty to mock simple by @amsanghi in #12
• Use create2 to deploy the RollupProxy and predict its address by @PlasmaPower in #5
• fix: resolve cyclic dependencies by @gzeoneth in #11
• update dirname in readme by @DZGoldman in #14
• chore(ISequencerInbox): Add Missing views by @shotaronowhere in #15

Full Changelog: v1.0.2...v1.0.3-beta.0