Rename AwaitUtils and ExceptionUtils following plural convention

[andreacalia]

At the moment there a bit of discrepancy between util classes. Let's homogenize them:

• AwaitUtils --> Awaits
• ExceptionUtils --> Exceptions

If you don't have a better naming suggestion I'll apply this at some point :smile:

[andreacalia]

Fixed by @DaveWalsh01 and anyway improved in #38