Increase test coverage
Correct indentation for `write_goto_file`
Do not re-acquire file lock in the same run
Make sure access time and count is a number

Before, it was not guaranteed that there was anything useful in these
fields. Now they are converted to 0 if not convertible to int so that
any function that relies on these numbers can be sure that there is
an integer present.
Version 3.1.0
Use a proper timestamp when cleaning up
Fix a bug where adding directories fails

This was covered by the tests but I didn't run them. Wow.
Version 3.1.1
Map to real values to prevent programming errors

It always bothered me that the internal representation of the properties
was type-less (string-only). This is fixed now.
Unify comment style
Use old read to migrate from permissive format

Since the new read method introduced in 43a05415d46320c254 will
fail with the old permissive way of storing values, we need the old code
that reads the file and some migration code to migrate to the new,
stricter format.
Version 3.2.0
Fix naming issue
Version 3.2.1
Add 'clean' sub-command

Enables to clean-up old entries that you will not use anymore.
Version 3.3.0