v4.0 official

What's Changed

• add bootstrap, font, and icon CDN links
• fix placeholder on the input box
• fix initial time display on the footer
• display stargazers_count in repository component
• update .gitignore
• add fork label
• recommendation of editor extension

• fix: update UI and add accessibility features by @thuongtruong1009 in #17
• fix: update label and extension by @thuongtruong1009 in #22
• [ImgBot] Optimize images by @imgbot in #23

New Contributors

• @imgbot made their first contribution in #23

Full Changelog: v3.0...v3.1