Ignore input lines starting with # (comments)

[walfie]

Readline (and thus rlwrap) has the ability to comment out the current
input line by pressing esc followed by #. However, kubectl-repl will
execute this as kubectl #insert comment here which shows the help
text. This updates the repl to ignore lines beginning with #.

[Mikulas]

Interesting. Currently this almost works as it leaves the interpretation on the underlying shell such as # prod test ; # echo foo (which is hardcoded to bash #2). But that is explicitly handled with the ; prefix.

We might consider adding the # to the shell builtin instead. https://github.com/Mikulas/kubectl-repl/blob/master/main/builtin-shell.go#L14

[Mikulas]

Awesome, thank you very much :)

[walfie]

That makes sense, I was wondering about that as well. I've pushed a commit that moves it to the builtin shell.

Also included a minor whitespace handling change -- I noticed TrimSpace also trims newline characters, and there was an existing call to trim newlines above, so I just combined them.