* Update reline-0.5.7

* Update irb-1.13.1

(https://github.com/ruby/irb/pull/784)

* Page evaluation result's output

This will make it easier to work with long output that exceeds the terminal's height.

* Use consistent TERM in rendering tests

This makes sure we get consistent result on all platforms.

https://github.com/ruby/irb/commit/4fedce93d3

(https://github.com/ruby/irb/pull/789)

If `output_modifier_proc`'s `complete` arg is true, it means the input is
submitted. In that case, debugger hint doesn't provide value to users
and adds noise to the output. So we hide it in such case.

https://github.com/ruby/irb/commit/f86d9dbe2f

test_autocomplete_with_multiple_doc_namespaces
(https://github.com/ruby/irb/pull/786)

https://github.com/ruby/irb/commit/85c6ddeb7d

(https://github.com/ruby/irb/pull/768)

When user enters irb:rdbg session, they don't get the same hint that the
`debug` gem provides, like

```
(rdbg) n    # next command
```

This means that users may accidentally execute commands when they want to
retrieve the value of a variable.

So this commit adds a Reline output modifier to add a simiar hint:

```
irb:rdbg(main):002> n # debug command
```

It is not exactly the same as `debug`'s because in this case the importance
is to help users distinguish between value evaluation and debugger command
execution.

https://github.com/ruby/irb/commit/fdf24de851

(https://github.com/ruby/irb/pull/764)

https://github.com/ruby/irb/commit/07e4d540cc

(https://github.com/ruby/irb/pull/743)

* Use IRB's own doc for doc dialog tests

* Run doc dialog tests for older Rubies too

* Remove unnecessary CI setups

https://github.com/ruby/irb/commit/97a2b86f0a

(https://github.com/ruby/irb/pull/699)

https://github.com/ruby/irb/commit/9b4aea753b

(https://github.com/ruby/irb/pull/685)

https://github.com/ruby/irb/commit/66e69fa0dc

(https://github.com/ruby/irb/pull/683)

* Add a test case for Ctrl-C handling

* Test symbol aliases with integration tests

There are a few places that also need to check symbol aliases before
`Irb#eval_input`. But since the current command test skip them, we
don't have test coverage on them.

* Move each_top_level_statement and readmultiline to Irb

This will save RubyLex from knowning information about commands and aliases.

https://github.com/ruby/irb/commit/69cb5b5615