Don't check for xpath if css selector is set
Test case and fix
Create testcase to show intention
Let haveFriend() to receive friend's actor class

This fixes #1386.

Passing an actor class is useful to create a friend with specific role, that is
implemented with step object like this:

    $admin = $I->haveFriend('admin', 'AcceptanceTester\AdminSteps');
    $admin->does(function(AcceptanceTester\AdminSteps $I) {
      $I->approvePost();
      $I->seeNewPostMessage();
    });

The original $I and $admin both can be specialized to their roles.
Add docstring
Load firefox profile from suite config.
Delete blank line.
Improve firefox profile loading.

Check given firefox profile for existence before setting it as WebDriver capability.
run included suits only if they really specified
Fix Friend class to allow multiple MultiSession modules to run properly
Typos fix
added roboci commands into RoboFile
Merge branch '2.0' of github.com:Codeception/Codeception into 2.0
updated robofile
added composer install to travis.yml
Merge pull request #1422 from TomaszKane/2.0

Typos fix
Merge pull request #1394 from tomykaira/friend_with_steps

Friend with steps
updated changelog
Merge pull request #1367 from Eye4web/webdriver-selector-fix

Don't check for xpath if css selector is set
Merge branch '2.0' of github.com:Codeception/Codeception into 2.0