fix: multiple places

Remove misplaced <td> in algo.js.
Make items <select> become 'disabled' if their "available" is 0.
Fix footer section.
feature(homeFirst): implement 家因(homFirst) in saveFile.js and loadFile.js
feature(homeFirst): add algorithm for homeFirst, add customizable fontColors[] for each type of students.
feature(colorBlocks): add colorBlocks