- Print the test name and data after the plan line

- Split on the plan line rather than on comments

  + That makes tap-filter more suitable to filter TAP output generated by other
    TAP producers.

  + However, the filtered output deletes the plan line and adds a blank line in
    its stead.  This suits our use-case of interactive test runs.

For human readers' benefit.

./.editorconfig is already set correctly.

Useful in piping Travis CI output through tap-filter manually.

Has room for improvement; for now, I use it with CTRL-W_f.

tee(1) truncated $fname.  Fortunately, the data that got truncated had just
been `git add`-ed, so no harm was done.

Thanks Daniel for the set -- suggestion.

This reverts commit ba2d8fcf76.

Breaks 4.3.12 and .11

This would have caught #593.

Required for TAP compliance in case the output ever contains '#' or '\n'.

Stylistic tweaks only; no functional change, no effect on TAP compliance.

Needed for next commit.

The new failure mode is:
.
    Running test main
    Bail out! On './highlighters/main/test-data/glob.zsh': Either 'PREBUFFER' or 'BUFFER' must be declared and non-blank
    Bail out! On './highlighters/main/test-data/glob.zsh': output on stderr
    Running test pattern

Fixes #478.

Remove superfluous single quotes around the second hyphen.

Closes #291.