minor improvements

- README:
  - Add RTL

- examples/configuration.nix:
  - Fix comment

- btcpayserver.nix:
  - Use nbLib.addressWithPort
  - Embed optionalString like the other optionalStrings

- clboss.nix:
  - Improve description

- clightning.nix:
  - Option `extraConfig`: Add example, improve description.
  - Disable `log-timestamps`. Timestamps are already logged via journald.
  - Simplify `preStart` script

- electrs.nix:
  - Use `port` description wording like in other services.

modules/clightning-plugins/clboss.nix

@@ -9,7 +9,9 @@ let cfg = config.services.clightning.plugins.clboss; in
       type = types.ints.positive;
       default = 30000;
       description = ''
-        Specify target amount (in satoshi) that CLBOSS will leave onchain.
+        Target amount (in satoshi) that CLBOSS will leave on-chain.
+        clboss will only open new channels if this amount is smaller than
+        the funds in your clightning wallet.
       '';
     };
     package = mkOption {