o Code simplification and refactoring (shared random, dirauth):
    - Change many tor_assert() to use BUG() instead. The idea is to not crash
      a dirauth but rather scream loudly with a stacktrace and let it continue
      run. The shared random subsystem is very resilient and if anything wrong
      happens with it, at worst a non coherent value will be put in the vote
      and discarded by the other authorities. Closes ticket 19566.