Pretty-print statistics for online

Now statistics are printed as a json object.

Statistics:
{
    "edgeCoverage": 100,
    "edgesNotVisited": [],
    "totalCompletedNumberOfModels": 1,
    "totalFailedNumberOfModels": 0,
    "totalIncompleteNumberOfModels": 0,
    "totalNotExecutedNumberOfModels": 0,
    "totalNumberOfEdges": 1,
    "totalNumberOfModels": 1,
    "totalNumberOfUnvisitedEdges": 0,
    "totalNumberOfUnvisitedVertices": 0,
    "totalNumberOfVertices": 2,
    "totalNumberOfVisitedEdges": 1,
    "totalNumberOfVisitedVertices": 2,
    "vertexCoverage": 100,
    "verticesNotVisited": []
}

Status: True

Expected:

Statistics:

  Model Coverage..................100%
  Number of Models...................1
  Completed Models...................1
  Failed Models......................0
  Incomplete Models..................0
  Not Executed Models................0

  Edge Coverage....................72%
  Number of Edges...................11
  Unvisited Edges....................3
  Visited Edges......................8

  Vertex Coverage.................100%
  Number of Vertices.................7
  Unvisited Vertices.................0
  Visited Vertices...................7

Status:  PASS