- Add license headers to source files (years based on commit dates)
in `src/test` as well as `qa`
- Add `README.md` to `src/test/data` specifying MIT license
Fixes#3848
Add a function `WaitBlocks` to wait for blocks to propagate to all three
nodes, and use this instead of waiting a fixed time of one second.
Fixes#3445.
qa/rpc-tests/wallet.sh runs a three-node -regtest network,
generates a fresh blockchain, and then exercises basic wallet
sending/receiving functionality using command-line RPC.