This change include the show load of loadv2 and some bug fix of loadv2.
Firstly, the show load will perform both load and loadv2 info. According to loadv2, the ETL progress of loadv2 is N/A during the period of loading.
Secondly, the loadv2 will be created when version of property is v2.
This is a temporary property which will not influence the old broker load.
After the loadv2 is finished, the default load will be changed to loadv2.
Finally, there are some bug in LoadingTaskPlanner fixed by this change.
* Add streaming load feature. You can execute 'help stream load;' to see more information.
Changed:
* Loading phase of a certain table can be parallelized, to reduce the load job execution time when multi load jobs to a single table.
* Using RocksDB to save the header info of tablets in Backends, to reduce the IO operations and increate speeding of restarting.
Fixed:
* A lot of bugs fixed.
