_sslverify.problemsFromTransport should be deprecated

[therve]

It's obsolete, but we should first remove its use in amp.

[exarkun]

(In [24195]) Branching to 'delete-problemsFromTransport-2874'

[exarkun]

(In [24196]) remove usage of problemsFromTransport from amp and then remove problemsFromTransport and all related support code

refs #2874

[exarkun]

It's removed. There's one small change in behavior. AMP IBoxReceivers now get the underlying OpenSSL exception passed to their stopReceivingBoxes method instead of an OpenSSLVerifyError (which was never exposed publically).

The underlying OpenSSL exception has more useful information in it, so this seems like an improvement to me. The most likely way this could break someone's program is if they imported OpenSSLVerifyError from the private twisted.internet._sslverify and did type checking on exceptions. That exception is no longer defined, so they'll get an ImportError.

Build results are here:

 http://buildbot.twistedmatrix.com/boxes-supported?branch=/branches/delete-problemsFromTransport-2874&num_builds=1

[therve]

Please merge.

[exarkun]

(In [24403]) Merge delete-problemsFromTransport-2874

Author: exarkun Reviewer: therve Fixes: #2874

Remove the private problemsFromTransport API which exposed OpenSSL errors. This API was redundant with IProtocol.connectionLost, which is called with a Failure wrapped around an OpenSSL.SSL.Error if there is a problem with SSL which results in the connection being lost.

AMP is also changed to use the failure passed to connectionLost rather than problemsFromTransport.