sslutil: document and slightly refactor validation logic This main purpose of this patch is to make it clearer that fingerprint pinning takes precedence over CA verification. This will make subsequent refactoring to the validation code easier to read.

sslutil: require a server hostname when wrapping sockets (API) All callers appear to be passing the hostname. So this shouldn't break anything. By specifying the hostname, more validation options from the ssl module are available to us. Although this patch stops short of using them.

sslutil: move and document verify_mode assignment Consolidating all the SSLContext options setting makes the code a bit easier to read.

tests: use --insecure instead of web.cacerts=! --insecure is the proper and documented way to do this. The end result is the same: dispatch will set web.cacerts to ! when --insecure is passed. This patch is necessary to refactor handling of web.cacerts in upcoming patches.

help: remove references to "Python 2.6 or later" We require Python 2.6. So there is no value to these docs.

commands: make --rev and --index compatible in debugobsolete

tests: enable import checker for tests/**.py files Several known-bad files are excluded as they couldn't be trivially fixed. In principle, we should fix them first, however, it would have more risk to keep Py3k porting going without the test coverage. Still contrib/**.py aren't covered, which needs another round.

tests: stop direct symbol import of mercurial modules in test-status-inprocess