Add noqa support for H201 (bare except)

This'll be nice to have in high-level exception handlers that really do want
to catch *everything*

For example, Swift has some error handling code that is intended to
prevent exceptions from ever getting back to the user.  Because we
don't know what exception classes a third-party lib might raise
(including ones that might not inherit from Exception), it is not
possible to enumerate all of the possible exceptions so a bare
except: is the only reasonable option.

Change-Id: I4b44185df6b43316446b37225741523c7c829a3f
(cherry picked from commit 56c491c0e27e4625b25bfb60ab8d8f2b64f22d6d)
Make H202 check honor pep8 #noqa comment

Several other checks allow for skipping lines with the standard pep8
 #noqa comment. This patch adds this for the H202 rule (don't use
assertRaises(Exception) as it may be too broad).

Change-Id: I134881298c0a42825764049667aa5b09652935ea
(cherry picked from commit e7d688c22901386dfcb7b20b1d1f1d474112f470)