chore: config assets for multiple chains

- lightning config
- env vars
- bitcoin.conf for different networks
- copy configs in lightningd repo
Signed-off-by: Lakshya Singh <lakshay.singh1108@gmail.com>

assets/regtest-config

@@ -0,0 +1,9 @@
+network=regtest
+bitcoin-rpcuser=rpcuser
+bitcoin-rpcpassword=VLSsigner1
+bitcoin-rpcport=38332
+log-level=info
+max-locktime-blocks=288
+important-plugin=/usr/bin/clboss
+clboss-auto-close=true
+bind-addr=0.0.0.0:19846