More examples: this simply tab-complete example can be added to the official examples

[rubyFeedback]

First the code:

---

require 'reline'
alias e puts

prompt = '> '

# ============================================================================ #
# === SHALL_HISTORY_BE_USED
# ============================================================================ #
SHALL_HISTORY_BE_USED = true

STATIC_LIST = [
  'search',
  'download',
  'open',
  'help',
  'history',
  'quit',
  'url',
  'next',
  'clear',
  'prev',
  'past'
].sort

Reline.completion_append_character = ' '
Reline.completion_proc = proc { |entry|
  STATIC_LIST.grep(/^#{Regexp.escape(entry)}/)
}

begin
  loop {
    user_input = Reline.readline(prompt, SHALL_HISTORY_BE_USED)
    e "The user input was:\n#{user_input}"
    p Reline::HISTORY.to_a
    case user_input
    when 'q','quit','break','exit'
      break
    end
  }
# To exit, type the key combination: Ctrl-C
rescue Interrupt
  exit 0
end

---

I modeled this after the multi-readline example and the ruby readline example.

It is a simply tab-complete example. If the user types e. g. 's' and then hits the
tab key, it will complete to 'search ' including the trailing ' '.

I think we should have standalone examples for all this core functionality somewhere
in the repository. It is quite impossible to find useful documentation about reline,
in part because Google search is bad, but in part because reline is still fairly new
and people don't seem to write a lot of documentation in ruby anymore - not sure
why. Without documentation it is harder to find useful things.

I am still trying to adapt an example for tab-completion on words that follow after
the initial command, e. g. to tab-complete on files and directories in the local
directory. I know I had this for readline, but I can not find it right now - let's see
if I can follow up with another example here.

I give full explicit permission to include this example in this form, or in any other
modified variant you folks see fit. I do not require any attribution e. g. you can
mark this with any authors as you see fit, e. g. "reline developers" would be perfectly
fine but so would it be perfectly fine to credit tompng or the ruby readline authors,
I really don't mind in any way, shape or form here. To me the only important part
is that we manage to improve the documentation of ruby-based projects in general.
So many projects have very poor documentation and lack examples. This is very
bad. If ruby wants more users then we need better documentation; Burdette
understands this very well, as he is very active in different ruby projects. We need
more folks who learn from him there.