Add CPU, I/O and memory consumption for an Azure SQL DB

[mstuefer]

I noticed that my PR is actually very similar to the one of @martinknafve. (Sorry I didn't look at the other PRs before adding this change) But still, this one uses sys.dm_db_resource_stats which is more granular (15sec updates) instead of the sys.resource_stats (300sec updates). Furthermore as you've already seen the other PR is not V12 compatible, since Microsoft changed the DMV, this one is for V12, I thought maybe it is useful for others too and therefore the PR. :-)

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