Add flag to hide stacktraces of caught exceptions

Motivation

GHC prints callstacks for all exceptions caught and uncaught when +RTS -xc. Some libraries rely main logic on throwing/catching exceptions, which is hidden behind library facade, but callstack analysis is very important tool in program debugging and stacktraces of exceptions causing problems are mixed with informative stacktraces.

An infinite recursive function in my app floods log constantly with such stack traces and I cannot spot anything really suspicious.

Proposal

Provide api to control stacktrace logging.