rewriting stuff in lab3
update Day 4
Update day4.md
Added FAQ on the desugar rule failing in the MiniJava editor
Merge pull request #4 from thegeman/desugar-question

1 bonus point.
Update for day 5 lab.
Update day5.md
Update day5.md
Update day5.md

Change start symbol to Program, which is the start symbol being used this year.
Update day5.md

Clarify that referencing the main class is also not allowed.
Update day5.md
Clarified hiding in the objectives
Update day4.md

Uop -> UnOp, Bop -> BinOp
Update assignment 6 for this year's situation.
Update day6.md

Remove redundant explanation of new initial project.
Update day6.md

Clarify initial project contents.
Update day6.md
Add link to assignment 6.
Update day6.md

Correct imports
update builders