Version 2.0.0
Add AngularJS.
Create new popup page using AngularJS.
Create new option page using AngularJS.
Add Google Scholar.
Merge branch 'new-option' into develop
Merge branch 'scholar' into develop
Remove IggyJs.
Remove disused CSS file.
Remove KlassJS.
Fix option page bug.
Revise the image permission.
Revise Preference constructor.
Create Badge constructor.
Fix badge bug.
Refactor codes around context menus.
Add context menu setting items to the option page.
Fix a bug of content scripts.
Merge branch 'badge' into develop
Merge branch 'contextmenu' into develop