5.0 beta1: Create Index

In 5.0, Index create will retry building the index in background, if indexer is currently busy building another index. An example of error message returns to the user is

{

"code": 5000,
"msg": "GSI CreateIndex() - cause: Fail to create index or replcia on some or all indexer nodes. Error=Fail to build index. Index build will retry in background.\n.",
"query_from_user": "create index country6 on `travel-sample`(country)"
}

Indexer will retry until index build succeeds.  If the user drop the index, then indexer will stop retrying.