Fully working tool for basic LND commands.

[tee8z]

• adds ability to use multiple doppler files on the same cluster with SKIP_CONF
• enables "OPEN_CHANNEL", "SEND_LN", "SEND_ON_CHAIN", "CLOSE_CHANNEL" for LND node
• enables "MINE_BLOCKS" on bitcoind node
• starts to add a visualizer that shows how to call the lnd nodes from the browser
• enable "LOOP" command that can run for a given number of iterations, forever with a sleep interval, or given number of iterations with a sleep in between
• cleans up threading logic to gracefully shut them down
• choose a different logging library to make it easier to track logs across threads