Added a general purpose try-catch around handle() for instances where an exception would cause the server to never return a response. At some later date we would possibly still wish to provide a custom hook for dealing with 500s. Also note, after an exception is caught, the generated 500 response is still sent to middleware handlers
Merge branch 'try-catch-handle' of https://github.com/acron0/crow into acron0-try-catch-handle

Conflicts:
	amalgamate/crow_all.h
Merge branch 'acron0-try-catch-handle'