Add building class
Merge branch 'master' of https://github.com/andymurph/traintastic
Add a method to calculate trip distance.

[Closes #2]

Squashed commit of the following:

commit 1c36daaf981a5a60744db0316ec1d4092fc7dc6a
Author: Andy Murphy <mrajmurphy@gmail.com>
Date:   Fri Dec 6 15:22:31 2013 -0600

    Add comment for ma bro

commit ddeef52343c942dc9d14a5475359002ac69a2dac
Author: Andy Murphy <mrajmurphy@gmail.com>
Date:   Fri Dec 6 15:17:43 2013 -0600

    Add trip distance method

commit ab4476fa23fb3eeeba24416763a5f2cb6aed6685
Author: Andy Murphy <mrajmurphy@gmail.com>
Date:   Fri Dec 6 15:12:00 2013 -0600

    Fix bug. Move calculate_speed method into train class

commit 165596fecb1f8e9b5b0983b65b8cc9db2570081b
Merge: f9add8d 5af14f0
Author: amhayslip <amhayslip@gmail.com>
Date:   Fri Dec 6 15:01:49 2013 -0600

    Merge remote-tracking branch 'origin/master' into calculate_trip_time

    Conflicts:
    	train.rb

commit f9add8d6508cbb342af5ddb504015df4c82018c9
Author: amhayslip <amhayslip@gmail.com>
Date:   Fri Dec 6 14:50:50 2013 -0600

    Add trip duration method