WaniKani Lesson User Synonyms 2: Kumi fork
Adds User Synonyms to the lessons page. Adds User Synonyms and Notes to unlearned item pages. This is an update of the version by irrelephant (0.2.3), and adds the function to add synonyms during the quiz too. Irrelephant's version was in turn an update of the version that was originally provided by @kobayashi (Takuya Kobayashi) and has been adapted to work with a newer version of WaniKani. The original "WaniKani Lesson User Synonyms" in version 0.1.2 has been broken since November 2017.