[travis] Added sudo requirement for running riak-admin commands. [travis] Added riak-admin commands to create and activate test bucket.
[travis] Added sudo requirement for running riak-admin commands.
[travis] Added riak-admin commands to create and activate test bucket.

brianfrankcooper/YCSB,cricket007/YCSB,manolama/YCSB,jaemyoun/YCSB,leschekhomann/YCSB,ChristianNavolskyi/YCSB,madhurihn/YCSB_ToyDB,manolama/YCSB,leschekhomann/YCSB,manolama/YCSB,ChristianNavolskyi/YCSB,zyguan/ycsb,leschekhomann/YCSB,madhurihn/YCSB_ToyDB,brianfrankcooper/YCSB,ChristianNavolskyi/YCSB,brianfrankcooper/YCSB,madhurihn/YCSB_ToyDB,cricket007/YCSB,ChristianNavolskyi/YCSB,jaemyoun/YCSB,jaemyoun/YCSB,cricket007/YCSB,madhurihn/YCSB_ToyDB,leschekhomann/YCSB,manolama/YCSB,jaemyoun/YCSB,cricket007/YCSB,zyguan/ycsb,brianfrankcooper/YCSB,zyguan/ycsb,zyguan/ycsb