Implemented tests and fixed default timeout value to not soo huge

[dbalabka]

It fixes wrong huge default value for timeout that was introduced in #429

• be sure that Travis tests works fine

IMPORTANT! To prepare ssh tests, I have to use sudo: required that means that all tests will run on old Travis infrastructure not container-base

[oanhnn]

Sorry @torinaki ,
This is an important issue, it introduces error in version 3.0.7 and 3.0.8.
I want to merge this PR without adding tests (all tests will be reviewed by @Elfet or other maintainer).
Please split this PR to two PR:

• fixed default timeout value
• adding tests
  Thank you!

[antonmedv]

Thanks for fix! 🍻
I think @oanhnn is right, but now we need to fix it as soon as possible.
So i merge this PR.
@torinaki is it possible to implement this tests, but on new travis dockers?

[dbalabka]

@Elfet , @oanhnn here is PR #438 . Manually tested both cases(w/o bug, with bug)

[dbalabka]

@Elfet about tests implementation on new travis docker. I was searching on github for already existing examples, but unfortunatly no luck. My current implementation was based on phpseclib implementation.
Currenlty i have few ideas where we should drip. One of them the most real is:
Try to install SSH server on travis docker. It should listen on 127.0.0.1(it is possible). For example we can try to install binary of openssh server: https://help.ubuntu.com/lts/serverguide/openssh-server.html .