Add Clues features

[clpetersonucf]

A request came in from a faculty member that provides a solid pedagogical improvement over Word Search's current implementation: instead of providing the words outright, clues are provided and students must guess the word and locate it in the Word Search puzzle. Hint options should be provided as well, much like Crossword:

1. An optional hint dialog to provide hint text for the word
2. An automatic hint option that identifies the first letter of the word and highlights them in the letter grid

The current version (where words are provided directly) must continue to be supported. The clue feature should be an optional toggle instead of replacing the existing implementation outright.