Mnemonics worksheet from lectures
wordOccurences implementation that passes tests
sentenceOccurrences in terms of wordOccurrences
pre-computer anagram lookup map, dictionaryByOccurrences
wordAnagrams implementation using the occurrence-list -> words table.
Use default anagram list of 'empty' when looking up a word's anagrams
combinations implementation, similar to the 'encode' function from lectures.

Don't like the hard coded List(), but it works.
subtract using map updates and foldLeft.
sentenceAnagrams in terms of previous functions.