merged conflicting commits

Signed-off-by: Nathan Hsieh <hsieh.nathan@gmail.com>
Squashed commit of the following:

commit 3f9e9185fe7ee51f2fe55f0fc0d4fffdc4f289dc
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Mon Oct 6 10:57:35 2014 -0700

    changed the title of back buttons

commit f86934424e85931ec293e711ceaa93ee920828fb
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Mon Oct 6 10:53:15 2014 -0700

    Finished level 2, refactored tests

commit 8f502bce05293cccaf200b69ce5f5826eee72484
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Mon Oct 6 08:52:37 2014 -0700

    stylized better and added level 2

commit 07b2276b346c34c0cc0faa57500c40e120e77888
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Fri Oct 3 18:17:29 2014 -0700

    broke tutorial tests styles

commit 35d84147dc2f65b0ffeea5faf304add903219b1e
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Fri Oct 3 17:23:48 2014 -0700

    structured test level1 md file

commit 808d01b0d55d67eb1017f290a29da6c7d38565f2
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Fri Oct 3 17:15:46 2014 -0700

    Modified files and integrated tutorial through new page

commit 0f0093f2882489c3eeb6f8870f2b8aa64dc939a3
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Thu Oct 2 14:34:44 2014 -0700

    more refactoring

commit 5a9b98e55ebd455ccf2c0ced20f984545a0b6d71
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Thu Oct 2 11:46:58 2014 -0700

    clean js code

commit af3bbd8d5e1dffdaa1780f83b909ff566906e513
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Thu Oct 2 11:26:39 2014 -0700

    level 1 cleanup

commit c4852a7766ab4fbd978d65c8352ace05eb427ef5
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Thu Oct 2 11:20:17 2014 -0700

    fixed up fill-in level1

commit 7f02d80942549dec9c05f784b777fcb32d5bb81b
Author: Nathan Hsieh <hsieh.nathan@gmail.com>
Date:   Wed Oct 1 17:45:42 2014 -0700

    added dockerfile tut, stylized lesson1 Questions

Signed-off-by: Nathan Hsieh <hsieh.nathan@gmail.com>
added fixes to address comments

Signed-off-by: Nathan Hsieh <hsieh.nathan@gmail.com>
Merge pull request #8419 from nhsiehgit/dockerfiletut

Dockerfiletut