Remove -t and -tt functionality from ironpython

[dc366]

This is a PR for issue #982, which removes console flags for indentation inconsistency. As suggested by @BCSharp, the arguments parser ignores -t and -tt by taking no action on them.

I have not updated the test suite. I see that the relevant test is test_t() in test_stdconsole.py. Curiously, the test suite only fails on net46 after I make these changes.

Your comments are appreciated!

• Ignore -t and -tt command line arguments
• Remove -t and -tt from command line help
• Remove sys.flags.tabcheck
• Remove PythonOptions.IndentationInconsistencySeverity and related code

[dnfadmin]

All CLA requirements met.

[slozier]

Thanks for the PR.

Unfortunately I think you removed some of the wrong code paths. I guess in the description it should have been noted that the expected behavior is what we would have with the -tt option turned on. That means we should keep the code that would run with IndentationInconsistencySeverity == Severity.Error.

[slozier]

As for test_stdconsole only failing on net46 it's because the whole suite is disabled in .NET Core.

[dc366]

I moved the initialization of indentFormat to the State constructor. In testing on my end, there are a few new test cases which fail as a result of this change.

I realized I went beyond the scope of the original issue, from simply ignoring the command line flags for indentation warnings to forcing the tokenizer to check for inconsistent indentation (though this is the desired behavior in Python3). I am not sure I have the ability to debug the behavior of the new ReadNewline() function without spending a lot more time. Let me know what you think a reasonable stopping point is.

[slozier]

No problem! This is great (and exactly what I had in mind as resolution of the issue).

Most of the test failures were expected with this change and I amended the tests to pass. It looks like there was one bug in the original ReadNewlineWithChecks which I fixed.

[slozier]

Thanks for the PR!