v0.6.2

Bugfix release for fixing:

* `imag-diary` did not recognize the "-d DIARY" setting.
* A parsing error in `libimagstore`, which caused the parsing of entries
  with a line "---" in the content part to fail, was fixed.
* The bugfix above introduced another bug which caused entries to be
  rewritten in one line when accessing them. This was fixed.
* `imag-diary` did not properly set "minute" and "second" when creating
  "hourly" or "minutely" entries.
* Version numbers for all crates as well as in the docs were updated to
  "0.6.2".