Added Git-Scanner for Web Exploitation Tools

[fabacab]

1. It is unclear what this tool offers that the existing Git ripping tools listed here already offer.
2. This tool is only 5 months old, which is relatively young (i.e., not very mature) in comparison to the others.
3. I suspect this was submitted mostly for participation in DigitalOcean's Hacktoberfest, which I am making an executive decision to explicitly opt-out of in order to avoid a barrage of spam. Opting-out will mean I will be automatically marking any PR I suspect is mostly motivated by the DO Hacktoberfest nuisance as "spam" unless another maintainer objects.

[HightechSec]

1. It offers more choices than the existing git ripping tools, Such as:
   • It can scan first before dumping, so you will not dump blindly
   • It works for mass scan/dump based on provided target list, so you have not to run it manual one-by-one if you got many target
   • It got more option like Scan and Dump at the same time, Scan only and Dump only.
   • And it will detected the folder that had "403 Forbidden" error and try to dump if the inside files/folder are not Forbidden
2. Yes it's only 5 months old, but from my side it's already got cover by.
   • Kitploit (https://www.kitploit.com/2020/06/git-scanner-tool-for-bug-hunting-or.html)
   • Hackin9 (https://hakin9.org/git-scanner-a-tool-for-targeting-websites-that-have-open-git-repositories-available-in-public/)
3. First of all, my main point is only to get some coverage for people using my tool for doing some pentest or bounty hunting, The hacktoberfest thingy? it's not my main point