fixed bug where if no patterns were entered into a misconception, you couldn't edit any of the patterns.
increasing unicorn workers
changed wording of misconception probabilities. instead of S it is now P and instead of H it is now HL
bypassing equation_images controller by insterting the codecogs.com url in at initial render time
adding correct_answers to class reports model. class reports now calculate the correct answers for each quiz and store that in the class reports model. class report now displays the correct answer for each question