minor fixes

- bitcoind: Remove obsolete defaultText
- clightning: Fix description
  Option `address` can't be used to specify a socket path because it's
  used explicitly as an IP address in many places.
- lnd: Break up overlong line
  This is required by commit `services: support 0.0.0.0/:: in `address` options`
- nix-bitcoin.nix: Formatting
- secrets: Improve descriptions

modules/lnd.nix

@@ -221,7 +221,9 @@ in {
         in [
           (nbLib.script "lnd-create-wallet" ''
             attempts=250
-            while ! { exec 3>/dev/tcp/${cfg.restAddress}/${toString cfg.restPort} && exec 3>&-; } &>/dev/null; do
+            while ! {
+              exec 3>/dev/tcp/${cfg.restAddress}/${toString cfg.restPort} && exec 3>&-
+            } &>/dev/null; do
               ((attempts-- == 0)) && { echo "lnd REST service unreachable"; exit 1; }
               sleep 0.1
             done