Merge pull request #23 from KimMinJeong/KMJ

Kmj
edit session authority
img responsive 적용
댓글 기능 수정
Merge branch 'master' of github.com:KimMinJeong/Collabo into board_main_contents

Conflicts:
	Board/templates/contents.html
Merge pull request #24 from KimMinJeong/board_main_contents

Board main contents
li -> table
before_request bye
db 관계 정리, pep8 적용
Merge pull request #27 from KimMinJeong/board_main_contents

Board main contents
modify DB relation