* 1.0
- Start release.
* 1.1
- Fixed file DO_NOT_MODIFY.txt.
* 2.1
- Rewrite the ADT's Trie/TrieNode according to the curse 2021/22.
* 2.2
- Added README.md.
- Adapted to course 22-23.
* 2.3
- Adapted to course 23-24.
* 3.0
- Added testing with ctest.
- Added support to utf-8 encoding.
- Adapted to course 24-25.
* 3.0.1
- Fixed exception message "Wrong input format." as "Wrong input format" when
an unexpected format is found unfolding a trie node.
* 3.1
- Rewrite to use operators <</>> to fold/unfold.
- Rewrite format to use '<string>' for symbols and prefixes.
- Adapted to course 25-26.
* 4.0
- Added support to compact a trie and working with a compact trie.
