Print stack trace on errors using libunwind

[tcm-marcel]

The idea: Print a stack trace on server side when exceptions get caught (stack trace from the time they were caught). Where is some old print stack trace code, which we want to replace with libunwind.

@mengranwo already tried this in #914 and #995, but failed because of a few (partly unrelated) errors she couldn't eliminate. I think we can give this PR another try, since a few of these things have been solved in the meantime.

• Try to apply Print out stack trace when throws an exception #995 to current master
• Cleanup exceptions and stack trace code

[a6802739]

@tcm-marcel , I'm new to this project, could I have a try for this?

[apavlo]

@a6802739 Go for it.