Listen does not treat 'sed -i foo' as a modification

[e2]

Command: e.g. sed -e 's/foo/bar' -i baz.rb

Expected: modified: ['baz.rb']
Actual: added: ['baz.rb']

The cause:

sed uses the same "overwrite file using move()" technique other editors use for saving files.

But this is not detected like other editor operations, because the sed temporary files created (e.g. sedq7eVAR) are not ignored (if they were, Listen would treat them specially).

Implementation:

The file temp file template used by sed is /sed[[a-zA-Z0-9]]{6}/, but it should not match likely words, like 'sedatives' or possible file names like 'sedan2010'.