Add a commit and compare view

[ikhoon]

Motivation:

Central Dogma UI does not provide a commit view or changes view between revisions.

Modifications:

• Remove a history tab in a file editor and add a commit view button instead.
  • The history tab didn't have a deep link for it.
  • As a result, we can't directly enter the history view from a URL
  • Addtionally, the orignal page wasn't preserved when we navigated pages back and forth.
• Add history view pages on /app/projects/<proj>/repos/<repo>/commits.
• Add a commit view page on `/app/projects//repos//commit/₩
• Add a changes view page on /app/projects/<proj>/repos/<repo>/compare/<head-rev>/base/<base-rev>
• Dependencies)
  • Add prismjs 1.29.0 for syntax highlights for the diff view.
  • Add react-diff-viewer-continued 3.4.0 for the beautiful diff UI.

Result:

You can now track changes using diff UI.

[ikhoon]

• History
• Changes
• Commit