liquid: drop the flat fee for mempool policy patch

[YusukeShimizu]

Elements releases have the mempool policy patch, so we should consider a minimum elements version.
After applying the patch, the minimum fee is set to 0.01.

• Once the version of the elements has been determined, update the version designation.
• Update glighting gelements: add GetNetworkInfo glightning#13
• Updated to match the above changes in reserved sat.
  • https://github.com/ElementsProject/peerswap/blob/master/peerswaprpc/server.go#L234
  • https://github.com/ElementsProject/peerswap/blob/master/clightning/clightning_commands.go#L392