Implement dates with range.
Organize tests.
Implement TimeLogs#range().
Preliminary range support.
Fix tests.
Reporter: hide productive time on non-productive days.
Improve appearance of ranges.
Show 'no entries' on its own line.
Simplify totals display.
Implement 't all'.
JsonReporter: support ranges.
Export utils in module.
Allow plugins via -u.
Tasks.
Tests fix.
Remove CSV reporter.
Release v0.1.0