Remove unnecessary Read- methods

* These were originally intended to separate the reading process for
  bipartite and adjacency graphs. It turned out that because AddEdge is
  the (only) common interface that both implementations share separation
  was not necessary

src/SparseTransform/Convert/IReader.cs

 using DataStructures;
 
-
 namespace SparseTransform.Convert
 {
     interface IReader
@@ -13,21 +12,5 @@ namespace SparseTransform.Convert
         public IGraph ReadGraph(String matrix);
 
         public DoubleMatrix ReadMatrix(String matrix);
-
-
-        /// <summary>
-        /// auxiliary method for transforming <c>matrix</c> in a bipartit graph
-        /// </summary>
-        /// <param name="matrix">input matrix string</param>
-        /// <returns></returns>
-        BipartiteGraph ReadBipartite(String matrix);
-
-        /// <summary>
-        /// auxiliary method for transforming <c>matrix</c> in a adjacency graph
-        /// </summary>
-        /// <param name="matrix"></param>
-        /// <returns></returns>
-        AdjacencyGraph ReadAdjacency(String matrix);
-
     }
 }

src/SparseTransform/Convert/MatrixMarketReader.cs

@@ -165,15 +165,5 @@ namespace SparseTransform.Convert
             }
             return firstDataLine;
         }
-
-        public BipartiteGraph ReadBipartite(string matrix)
-        {
-            throw new NotImplementedException();
-        }
-
-        public AdjacencyGraph ReadAdjacency(string matrix)
-        {
-            throw new NotImplementedException();
-        }
     }
 }
\ No newline at end of file