runtime/qio: use getcwd instead of getwd

Included code for handling errors.

Related to #325.
Update bug summary
Change method->function
Suppress notifications from modern mac testing.

This will avoid lots of notifications to regressions list. This should be
reverted once the nondeterministic failures are fixed.
Merge pull request #344 from thomasvandoren/new-mac-suppress-spammy-notifications

Suppress notifications from modern mac testing.

This will avoid lots of notifications to regressions list. This should be
reverted once the nondeterministic failures are fixed.
Update TRIAGE file with some new errors.
Merge pull request #345 from hildeth/master

Update TRIAGE file with some new errors.
Merge pull request #332 from fsouza/getcwd

runtime/qio: use getcwd instead of getwd [on behalf of fsouza]

getwd is deprecated in favor of getcwd.  Related to #325.
Default values for ref args should not be allowed, so turn this into
an "error message" future.
Slight change in bug summary to be more specific.
Add a future for default values for const ref arguments to functions.
Merge pull request #343 from sungeunchoi/test

Update a few futures

- Update text of test/functions/lydia/syntax-error-unclear-message*.future [reviewed by @lydia-duncan]
- Change test/functions/tzakian/implicit_arg_pass_by_ref.future  into an error message future
- Add test/functions/sungeun/const_ref_arg_default_value.future for default values for const ref arguments
io: add chown

Unfortunately it's not possible to test the happy path: only superusers
can call chown.