Update mining API (/v1a/mining_ws) #13
Description
The definite solution for the issue "Testnet is not mining blocks" is to get block templates from the newer mining API /v1a/mining_ws and apply the min and max timestamp constraints.
As the client for the new mining API was not available at the time, and this issue just affects the testnet, we decided to move forward with the intermediate solution in the PR #11 .