Make large numbers in tooltip easier to read

[JustinPealing]

See microsoft/azuredatastudio#2140

Large numbers on the tooltip are often very difficult to read. There are no commas used in the numbers, so it's difficult to tell 501 million from 5 million, for example. Also, sometimes scientific notation is used for very small numbers that is difficult for a human to read. (This problem also exists in SSMS.) Using commas in large numbers and avoiding scientific notation for small numbers (even at the expense of precision) would improve this quite a bit.