Clojurians Log v2

(added a table of available pod functions when repl starts up. but the docstrings in the code still needs lot of work)

Updated the babashka book section on child process and rewrote it to use babashka.process: https://book.babashka.org/#child_processes

Cross platform single file with deps Clojure JVM launcher script: https://github.com/babashka/book/issues/8

I cleaned up the main README.md as it was getting pretty lengthy and moved most of the content to https://book.babashka.org/ https://github.com/borkdude/babashka#babashka-book

If you think anything is sorely lacking from the README, I can add explicit links to the relevant part in the book. Let me know what you think.