Minimal Java Trie using LinkedLists
- add(CharSequence sequence) : adds a CharSequence to the Trie
- addAll(Collection<CharSequence> sequenceCollection) : adds a Collection of CharSequences to the Trie
- contains(CharSequence sequence) : returns true if the Trie contains a CharSequence
- remove(CharSequence sequence) : removes a CharSequence from the Trie preserving sub-sequences
- isEmpty() : returns true if the Trie is empty