Modify getNextTarget function parameters

A new parameter "origin"  is necessary for the getNextTarget call.
Refactorized test

Implemented a setUp method for initialize common objects used in tests.
Modify the getNextTarget call

Added the new parameter "origin" for the getNextTarget call
Added the new test

Added a new test for the DistanceRouter class.
Implemente the class

Implemented the DistanceRouter class