Comparing to current master, there is no substantial difference.

+-------------------------------------------------------------+----------------+------------------------------+
| Benchmark                                                   | bench_master38 | bench_issue200               |
+=============================================================+================+==============================+
| call interface (alternate, no conform, not provided)        | 395 ns         | 414 ns: 1.05x slower (+5%)   |
+-------------------------------------------------------------+----------------+------------------------------+
| call interface (no alternate, valid conform, not provided)  | 250 ns         | 240 ns: 1.04x faster (-4%)   |
+-------------------------------------------------------------+----------------+------------------------------+
| read __module__                                             | 45.3 ns        | 43.4 ns: 1.04x faster (-4%)  |
+-------------------------------------------------------------+----------------+------------------------------+
| query adapter (no registrations)                            | 3.23 ms        | 3.31 ms: 1.02x slower (+2%)  |
+-------------------------------------------------------------+----------------+------------------------------+
| query adapter (all trivial registrations)                   | 3.93 ms        | 4.40 ms: 1.12x slower (+12%) |
+-------------------------------------------------------------+----------------+------------------------------+
| query adapter (all trivial registrations, wide inheritance) | 43.3 us        | 45.5 us: 1.05x slower (+5%)  |
+-------------------------------------------------------------+----------------+------------------------------+
| query adapter (all trivial registrations, deep inheritance) | 43.2 us        | 46.9 us: 1.09x slower (+9%)  |
+-------------------------------------------------------------+----------------+------------------------------+
| sort mixed                                                  | 361 us         | 354 us: 1.02x faster (-2%)   |
+-------------------------------------------------------------+----------------+------------------------------+
| contains (populated dict: interfaces)                       | 61.3 ns        | 59.7 ns: 1.03x faster (-3%)  |
+-------------------------------------------------------------+----------------+------------------------------+

Not significant (13): call interface (provides; deep); call interface (provides; wide); call interface (no alternate, no conform, not provided); call interface (alternate, invalid conform, not provided); read __name__; read __doc__; read providedBy; sort interfaces; sort implementedBy; contains (empty dict); contains (populated list: interfaces); contains (populated dict: implementedBy); contains (populated list: implementedBy)

Only catch AttributeError instead of everything.

Fixes #200

Note that this does break a doctest in five.intid (it's expecting a TypeError but it now gets Acquisition's RuntimeError).

Ensure that objects that implement no interfaces still have Interface in iro and sro

Fixes #197.

Make the RO for InterfaceClass consistent and fix handling of the STRICT_IRO