Fix 1.8.7 syntax errors.
Allow any versions of listen < 2.0 and >= 1.3
Restrict mime-types gem to pre-2.0.

A coveralls dep has a '>=' dependency on mime-types.
Merge pull request #1665 from mojombo/downgrade-listen

Fix Listen implementation so master is compatible with 1.8.7
Update history to reflect merge of #1665