rename test file per ruby idiom
remove whitespace
rename some methods and variables to align with common ruby naming idioms
refactor goal_array into a Constant, since it should never change as long as we're sticking with a 3x3 puzzle
refactor start_array into a single initializer argument
rename #md to #manhattan_distance
whitespace
Refactor location method to not require passing in an array
#md_array method actually works
add comment to explain where this manhattan_distance nonsense came from
add readme