better shells flow and integration

[andrea crotti <andrea.crotti.0@gmail.com>]

Hi guys,
I'm in a weird mix situation in the way I use terminals.

I try to stay all the time inside emacs using shell-mode, which has the
great advantage of copying and pasting around easily and have all the
text transformation things in place.

However sometimes it's not all good, because:
- it's a bit hard to organize terminals in an easy and coherent way
  (could make more frames but it's a bit annoying)

- running long term processes is a bit risky if I have to restart the
  window manager or Emacs for some reason

- when some command has a LOT of output (sometimes unexpectedly) the
  shell buffer become unresponsive for a while (this is an issue with
  other repl as well), and in plus the shell becomes very slow after I
  have a lot of output there (thousands of lines).


So for some things I tend to use tmux and terminator, which are cool but
are not inside Emacs sadly.

Trying to find some ways to improve the flow:
1. is there a way to avoid these unresponsive moments and/or limit the
   number of lines in the shell (or other similar) buffer?

2. alternatively maybe can I integrate Emacs and tmux?
   Actually as soon as I thought about this I found a few things:
   http://bradylove.com/blog/2013/05/24/commanding-tmux-with-emacs/
   And a couple of packages in ELPA, so I'll try that out.

It would be nice to have a bidirectional integration though, so be able
to see also what's happening in the tmux sessions from Emacs.

Any suggestions?