[SPARK-4203][SQL] Partition directories in random order when inserting into hive table

When doing an insert into hive table with partitions the folders written to the file system are in a random order instead of the order defined in table creation. Seems that the loadPartition method in Hive.java has a Map<String,String> parameter but expects to be called with a map that has a defined ordering such as LinkedHashMap. Working on a test but having intillij problems

Author: Matthew Taylor <matthew.t@tbfe.net>

Closes #3076 from tbfenet/partition_dir_order_problem and squashes the following commits:

f1b9a52 [Matthew Taylor] Comment format fix
bca709f [Matthew Taylor] review changes
0e50f6b [Matthew Taylor] test fix
99f1a31 [Matthew Taylor] partition ordering fix
369e618 [Matthew Taylor] partition ordering fix