Support 'delete storage group <prefixPath>'

Currently, it seems that the user can delete all data and timeseries by 

delete timeseries root.*;

But this sql cann't delete all related storage groups. In addition, such an approach would be more time-consuming than simply deleting specified storage groups.

So I believe it's better for `delete storage group' command to support wildcard.

For example, all sgs and data can be deleted by one sql efficiently.

delete storage group root.*;

this sql is useful for some users in many scenarios, such as system cleanup during continuous testing;