GitZip for github

Description

Why GitZip:
- You DO NOT have to download the whole project just for those few files/dirs you need.

Usage:
1. In any GitHub public repos page.
2. two options:
a. Right-click (context menu) on the item and click download.
b. Double click on the items and click download button at bottom-right.
3. See the progress dashboard and wait for browser trigger download.
4. Get the ZIP file.

Get Token:
- If you see the "Rate Limit" warning message on progress dashboard, you should get the Github API access token for upgrade rate limit. GitZip provide a convenient way for it:
1. Click GitZip Extension icon on your browser.
2. Click "Normal" or "Private" link beside "Get Token".
3. Authorize GitZip permission on Github auth page.
4. Back to repo page of the beginning.
5. Continue to use.

About GA usage:
Collect the names of author, repo, folder, file to GA (Google Analytics), in order to observe the usage situation and know which repositories are suitable with this tool.

Revision:
0.4.2:
1. Handle the dark mode.
2. Fix the item detection lost during change page.

0.4.1:
Change the ways for fetching git_url, use link href instead of link id.

0.4.0:
Compatible with new Github UI.

0.3.5:
1. Use the suitable permissions according to Chrome Extension Policy.
2. Use alternative way to fetch current url as referrer.

0.3.4:
1. Remove unnecessary permission.
2. Fix date timezone offset bug.

0.3.3:
Pass token through http header. (Github says using access_token query parameter will be deprecated)

0.3.2:
Fix a error about "runtime.lastError" error.

0.3.1:
Fix a error about pjax region detection.

0.3.0:
1. Handle the API response error and shows the instructions.
2. Support contextmenu on items or page of repositories.