Features:

• Improve Admin / Users features.
• Improve Admin / Photos as card list view and support search.
• Add batch delete user's 10 photos in Admin / User / Edit.
• Add captcha_enable setting (default: false), for allows disable captcha feature.
• Hide captcha settings when captcha not enable.

Fix:

• Fix team destroy and add test;
• Fix admin / users / edit batch delete photos to use destroy method for fix that trigger photo delete callbacks.
• Delete avatar file after User soft_delete or destroy.
• Fix #1251 devise mailer with async.