Modify top-style

Modify sns-button move to bottom
Add page-header background-color fafafa and box-shadow
New file: app/views/plans/_sns_button.html.haml
Add title "オリジナルプランを 作成 し、みんなに 共有 しよう"
Modify style top-page

Modify style plan-list
Modify title attention
Modify area-tag postion
Merge branch 'master' into top-style
Modify app/views/plans/index.html.haml
Because path test
Add id="top-page-header"
Merge pull request #105 from RyuPiT/top-style

TOPページのデザイン変更