Data directory for "bet" for reading cashier/dealer and RPC API config info

[satindergrewal]

Right now bet is communicating with c-lightning and chips via CLI commands.

This must be updated to instead use RPC communication, so that bet does not rely on command line path settings etc and be working independently. RPC specific issue can be tracked here: #179

For "bet" specific data directory based on different platforms, I'd suggest to make a data directory for bet specific configuration files. Like for different OS, it should be like:

• Linux: $HOME/.chipsbet/
• macOS: $HOME/Library/Applications Support/Chipsbet/
• Windows: %AppData%\Chipsbet

And under this bet's data directory we can move files located from privatebet/config/ directory:

cashier_nodes.json
dealer_config.json

There we can also have the chipsbet.conf file created to get the RPC information for both c-lightning and Chips. Example:

CHIPS_RPC_IP=127.0.0.1
CHIPS_RPC_PORT=57776
CHIPS_RPC_USER=chip_rpc_username
CHIPS_RPC_PASSWORD=chips_rpc_password

# c-lightning only provides JSON-RPC socket, and no HTTP RPC API
CHIPS_C_LIGHTNING_RPC_SOCKET=/home/username/.chipsln/chips/chipsln-rpc