Improvements to the Panel of each Repository

[hehao98]

• GFI => Good First Issues. It is non-intuitive for users to understand this abbreviation
• Add more repository statistics (# of stars, contributors, and forks) so that the users can know the quality of the repository
• Add more issue-related and module-related metrics, and show them directly in the repo panel (instead of in the per-issue page, as this information is also important for newcomers.
• Add options to sort GFIs. Old issues may be harder to resolve while the latest issues may be easier or more relevant.
• Add a title showing "XXXX Recommended Good First Issues"
• The per-issue item can be revised to resemble a GitHub style look (e.g., at https://github.com/matplotlib/matplotlib/contribute), with issue labels, opened at, last update, etc. It is important to additionally show whether an issue has a pending PR, as those without pending PRs should be of higher priority for a newcomer willing to contribute.
• Clicking the issue number will cause the browser to switch to the GitHub issue page. This is unintuitive. It is better to use a dedicated "To GitHub" button instead.
• The user should be able to choose the issues per page. (To allow quicker issue browsing)

[hehao98]

[GFI-Bot] Predicted as Good First Issue with probability 52.29%.