Added pydev project config files
Added empty src package
Added script to perform tests in command line
added first version of Node object.

It has the logic that represent any 2Dpoint and links with other nodes
to represent A* graphs

It stores x,y coordinates, links with other nodes and euclidean distances with other nodes
Added tests over Node object
Added city object with addLink behaviour updated
creating a double link between nodes
Added tests over city
Added first version of citymap loading data from python dict.

Added exception handling checking format of input data of dict
Added test to check right behaviour loading citymap data
Added methods to load data from json format, a natural way to represent python dict
object to perform input/output processes
Added tests to perform loading from string and filename.

Added test to check save method
Added AStar object to solve A-Star algorithm from citymap.

It has been implemented with the algorithm of wikipedia:
```
    http://en.wikipedia.org/wiki/A*_search_algorithm
```

reconstruct path has been updated from recursive function to iterative
Added tests to check right behaviour of astarsolver with some
easy tests

Fixed bug in astar implementation detected in tests
Added test of astar exceptions
Added command line tool to solve a-star with config files as input