reckless tool usage sketches

gistfile1.txt

"reckless install <url>"
 - might turn simple names (.e.g summary) into references to the GH plugins repo
 - allow URLs to inside repos for GH plugins.

Technical:
 - if first run, creates ~/.lightning/reckless/, puts in empty "bitcoin.config" and 'include ../reckless/bitcoin.config' if not already in ~/.lightning/bitcoin/config
 - download and unpack/move into ~/.lightning/reckless/<subdir>
 - perform simple check (e.g. for Python, you can run the plugin normally and it should exit with status 0).
 - start up dynamically
 - if it works, add to reckless/bitcoin.config
 
Stretch goals:
- allow --regtest / --testnet and/or read default config to determine.
- follow requirements.txt for Python plugins
- support non-Python plugins
- allow them to contain reckless.config file:
  - can require specific CLN versions
  - can require other plugins
  - can disable other plugins
  - can specify non-dynamic (requires node restart to enable/disable)
  - specify if config options are required (prompt user?)
- support 'reckless upgrade [plugin-names...]' to d/l new plugin, test, and then replace.
- support 'reckless list'
- support 'reckless remove'