Modified for custom RPC

[IoanAlin]

Modified for custom RPC

[ethernity-cloud]

Hello,

Thank you for the contribution Alin, unfortunately the PR is incomplete. The following aspects have to be covered by the current pull request:

• This setting should be available at installation time, like all the other settings, so additional files have to be updated so any installation can have this configuration, similar to the IPFS host setting.
• Please use environment variables as the rest of the code does already, to keep compatibility with previous versions of the agent.

Thank you!