[New Chain] : Support of Arbitrum

[NelsonRodMar]

Gm

I'm using ether.actor and would love to have the support of Arbitrum.

[NelsonRodMar]

I've created a PR to add Arbitrum, waiting for review and accept : #36

[iainnash]

Hi! Haven't seen this, would be glad to add.

[NelsonRodMar]

Ahah no worries, everything should be good to be merged !

[iainnash]

Added