fix Graph partitionStrategy comment

Author: CrazyJvm <crazyjvm@gmail.com>

Closes #1368 from CrazyJvm/graph-comment-1 and squashes the following commits:

d47f3c5 [CrazyJvm] fix style
e190d6f [CrazyJvm] fix Graph partitionStrategy comment

graphx/src/main/scala/org/apache/spark/graphx/Graph.scala

@@ -107,14 +107,16 @@ abstract class Graph[VD: ClassTag, ED: ClassTag] protected () extends Serializab
   /**
    * Repartitions the edges in the graph according to `partitionStrategy`.
    *
-   * @param the partitioning strategy to use when partitioning the edges in the graph.
+   * @param partitionStrategy the partitioning strategy to use when partitioning the edges
+   * in the graph.
    */
   def partitionBy(partitionStrategy: PartitionStrategy): Graph[VD, ED]
 
   /**
    * Repartitions the edges in the graph according to `partitionStrategy`.
    *
-   * @param the partitioning strategy to use when partitioning the edges in the graph.
+   * @param partitionStrategy the partitioning strategy to use when partitioning the edges
+   * in the graph.
    * @param numPartitions the number of edge partitions in the new graph.
    */
   def partitionBy(partitionStrategy: PartitionStrategy, numPartitions: Int): Graph[VD, ED]

graphx/src/main/scala/org/apache/spark/graphx/VertexRDD.scala

@@ -182,8 +182,8 @@ class VertexRDD[@specialized VD: ClassTag](
   /**
    * Left joins this RDD with another VertexRDD with the same index. This function will fail if
    * both VertexRDDs do not share the same index. The resulting vertex set contains an entry for
-   * each
-   * vertex in `this`. If `other` is missing any vertex in this VertexRDD, `f` is passed `None`.
+   * each vertex in `this`.
+   * If `other` is missing any vertex in this VertexRDD, `f` is passed `None`.
    *
    * @tparam VD2 the attribute type of the other VertexRDD
    * @tparam VD3 the attribute type of the resulting VertexRDD