Fix assert_(not_)?empty for tuples using .format

Previously, the message for these was being generated using an expression like:
    message = '... %s ...' % iterable

Because the % operator interprets a tuple as a list of values to interpolate rather than a single value, using these assertions on tuples without exactly one value was raising exceptions about the format string. (Tuples with exactly one value just got a slightly incorrect error message.)

This commit fixes the problems and tests both assertions with both an empty and a non-empty tuple.
Make kwargs for messages in assertions consistent

`message` is a better name than `msg`
Add backwards compatibility and DeprecationWarnings for changed kwargs
Test that DeprecationWarnings are raised when using the `msg` kwarg
Tests to ensure we don't complain about a missing test path if --connect or --rerun-tests-file are passed, but do complain if those aren't passed.
Don't require a test path when passed --rerun-test-file
Add two more tests to make sure we don't complain about a missing test path if --replay-json or --replay-json-inline are passed.
Make arg parsing not complain about the lack of a test path when --replay-json or --replay-json-inline are passed
first failure wins
handle multiple errors
The tb formatter no longer sometimes returns lists
Merge pull request #181 from EvanKrall/no_filename_when_rerunning

Don't require a test path when running with --rerun-test-file, --replay-json, or --replay-json-inline
Merge pull request #163 from rlipman/consistent-assert-kwargs

Make kwargs for messages in assertions consistent
Fix pyflakes error with msg/message in assert_dicts_equal
Merge pull request #184 from rlipman/fix-pyflakes-assert

Fix pyflakes error with msg/message in assert_dicts_equal
seperate those tests
Merge pull request #183 from bukzor/buck-teardown-errors

Always show the tests' traceback.
Merge pull request #174 from Jebdm/fix_assert_empty_and_assert_not_empty_for_tuples

Fix assert_(not_)?empty for tuples using .format
improved coverage for sql-plugin error formatting. demonstrates derpy behavior with multiline errors
fix multiline error handling by sql plugin