py3: make files use absolute_import and print_function This patch includes addition of absolute_import and print_function to the files where they are missing. The modern importing conventions are also followed.

sslutil: don't attempt to find default CA certs file when told not to Before, devel.disableloaddefaultcerts only impacted the loading of default certs via SSLContext. After this patch, the config option also prevents sslutil._defaultcacerts() from being called. This config option is meant to be used by tests to force no CA certs to be loaded. Future patches will enable _defaultcacerts() to have success more often. Without this change we can't reliably test the failure to load CA certs. (This patch also likely fixes test failures on some OS X configurations.)

sslutil: pass ui to _defaultcacerts We'll use this shortly.

sslutil: change comment and logged message for found ca cert file Future patches will change _defaultcacerts() to do something on platforms that aren't OS X. Change the comment and logged message to reflect the future.

tests: better testing of loaded certificates Tests were failing on systems like RHEL 7 where loading the system certificates results in CA certs being reported to Python. We add a feature that detects when we're able to load *and detect* the loading of system certificates. We update the tests to cover the 3 scenarios: 1) system CAs are loadable and detected 2) system CAs are loadable but not detected 3) system CAs aren't loadable

update: teach hg to override untracked dir with a tracked file on update This is a fix to an old problem when Mercurial got confused by an untracked folder with the same name as one of the files in a commit hg was trying to update to. It is pretty safe to remove this folder if it is empty. Backing up an empty folder seems to go against Mercurial's "don't track dirs" philosophy.

rebase: move handling of obsolete commits to be a separate RR class method

rebase: move rebase finish logic to be a method of the RR class Rebase finish logic includes collapsing working directorystate into a single commit, moving bookmarks, clearing status and collapsemsg files, reporting skipped commits to the user and obsoleting precursors of the newly created commits.

rebase: move core rebase logic to be a method of the RR class

rebase: move local variable 'extrafn' to the RR class