print atos info message in CDRSymbolicator only if all addresses failed symbolication
stop leaking exception reason in CDRSpecFailure
Symbolicate exception call stacks

Example exception output with symbolication:

EXCEPTION CDRSpec some failing test
*** -[__NSArrayI objectAtIndex:]: index 4 beyond bounds for empty array
Call stack:
  ...
  *InvalidArrayAccess.m:13
  *CDRSpecSpec.mm:51
  ...
  *main.m:4
  ...
add CEDAR_SKIP_EXCEPTION_SYMBOLICATION
catch potential errors when running atos
provide better error messaging when symbolication fails
include CDRSpecFailure and CDRSymbolicator specs in OCUnit target
Make exception symbolication an opt-in feature
Merge pull request #64 from cppforlife/master

Exception symbolication