Added tests for AddCommand and DumpCommand
Added test for #call_editor
Ensure the generated test file is removed
Added test for HelpCommand
Added tests for CategorizeCommand
Added tests for CategorizeDaysCommand
Added CategorizeMonthsCommand test
Added CategorizeYearsCommand tests
Added EditCommand tests
Added tests for Month class
Merge pull request #72 from matthiasbeyer/add-tests

Add tests