Allow users to pick explorers

[jhenriquez]

Is your feature request related to a problem? Please describe.
No

Describe the solution you'd like
As a User I'd like to be able to configure or select a default explorer. E.g. Pick between:

• explorer.pokt.network
• poktscan.com

Describe alternatives you've considered
Current alternatives require the users to either use poktscan or copy the hash and go to the explorer they'd like.

Additional context
Add any other context or screenshots about the feature request here.