Fix Broken Links

[justindhillon]

Summery

There are multiple broken links in this project. Here is what I have fixed:

https://people.xiph.org/~greg/confidential_values.txt --> https://web.archive.org/web/20200502151159/https://people.xiph.org/~greg/confidential_values.txt

https://lab.getmonero.org/pubs/MRL-0004.pdf --> https://web.getmonero.org/es/resources/research-lab/pubs/MRL-0004.pdf

https://github.com/monero-project/bitmonero/blob/master/src/cryptonote_core/cryptonote_format_utils.cpp --> https://github.com/monero-project/monero/blob/master/src/cryptonote_basic/cryptonote_format_utils.cpp

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[justindhillon]

Thanks for the feedback @UkoeHB ! That commit has been removed. Ready to merge!

[UkoeHB]

Ok sorry, looked at this even closer and the remaining two files are bibliographies for already-published papers. Fixing those links should only be done when republishing the papers, which there are currently no plans to do.