- Add operator==() and operator!=() to Dictionary and write tests for these functions
- Increase coverage of unit tests for Dictionary and Parser
- Check for TODOs in source code

TODO:
- Add `operator==()` and `operator!=()` to Dictionary and write tests for these
  functions
- Make sure that dictionary keyvaluepairs are lexicographically sorted on the
  keys when inserting new elements
- Increase coverage of unit tests for Dictionary and Parser
- Check for TODOs in source code

Add requirement that keyvaluepairs in dictionaries are sorted
Add requirement that keyvaluepairs in dictionaries are sorted
