Fix dead links

CONTRIBUTING.md

@@ -11,11 +11,11 @@ Before we get into the details of contributing code, you should know there are m
  - [Help fellow users with open issues]. This can require technical knowledge, but you can also get involved in conversations about bug reports and feature requests. This is a great way to get involved without getting too overwhelmed! 
  - [Help fellow committers test recently submitted pull requests](https://github.com/rapid7/metasploit-framework/pulls). Again this can require some technical skill, but by pulling down a pull request and testing it, you can help ensure our new code contributions for stability and quality. 
  - [Report a security vulnerability in Metasploit itself] to Rapid7. If you see something you think makes Metasploit vulnerable to an attack, let us know!  
- - [Add module documentation](https://github.com/rapid7/metasploit-framework/wiki/Generating-Module-Documentation). New documentation is always needed and cleaning up existing documents is just as important! If you're a non-native english speaker, you can help by replacing any ambiguous idioms, metaphors, or unclear language that might make our documentation hard to understand. 
+ - Add [module documentation]. New documentation is always needed and cleaning up existing documents is just as important! If you're a non-native english speaker, you can help by replacing any ambiguous idioms, metaphors, or unclear language that might make our documentation hard to understand. 
 
 
 ## Code Contributions
-For those of you who are looking to add code to Metasploit, your first step is to set up a [development environment]. Once that's done, we recommend beginners start by adding a [proof-of-concept exploit from ExploitDB,](https://www.exploit-db.com/search?verified=true&hasapp=true&nomsf=true) as a new module to the Metasploit framework. These exploits have been verified as recreatable and their ExploitDB page includes a copy of the exploitable software. This makes testing your module locally much simpler, and most importantly the exploits don't have an existing Metasploit implementation. ExploitDB can be slow to update however, so please double check that there isn't an existing module before beginning development! If you're certain the exploit you've chosen isn't already in Metasploit, read our [writing an exploit guide](https://github.com/rapid7/metasploit-framework/wiki/How-to-get-started-with-writing-an-exploit). It will help you to get started and avoid some common mistakes.
+For those of you who are looking to add code to Metasploit, your first step is to set up a [development environment]. Once that's done, we recommend beginners start by adding a [proof-of-concept exploit from ExploitDB,](https://www.exploit-db.com/search?verified=true&hasapp=true&nomsf=true) as a new module to the Metasploit framework. These exploits have been verified as recreatable and their ExploitDB page includes a copy of the exploitable software. This makes testing your module locally much simpler, and most importantly the exploits don't have an existing Metasploit implementation. ExploitDB can be slow to update however, so please double check that there isn't an existing module before beginning development! If you're certain the exploit you've chosen isn't already in Metasploit, read our [writing an exploit guide](https://github.com/rapid7/metasploit-framework/wiki/Get-Started-Writing-an-Exploit). It will help you to get started and avoid some common mistakes.
 
 Once you have finished your new module and tested it locally to ensure it's working as expected, check out our [guide for accepting modules](https://github.com/rapid7/metasploit-framework/wiki/Guidelines-for-Accepting-Modules-and-Enhancements#module-additions). This will give you a good idea of how to clean up your code so that it's likely to get accepted.  
 
@@ -92,17 +92,17 @@ curve, so keep it up!
 [50/72 rule]:http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html
 [topic branch]:http://git-scm.com/book/en/Git-Branching-Branching-Workflows#Topic-Branches
 [draft PR]:https://help.github.com/en/articles/about-pull-requests#draft-pull-requests
-[console output]:https://help.github.com/articles/github-flavored-markdown#fenced-code-blocks
-[verification steps]:https://help.github.com/articles/writing-on-github#task-lists
+[console output]:https://docs.github.com/en/free-pro-team@latest/github/writing-on-github/creating-and-highlighting-code-blocks#fenced-code-blocks
+[verification steps]:https://docs.github.com/en/free-pro-team@latest/github/writing-on-github/basic-writing-and-formatting-syntax#task-lists
 [reference associated issues]:https://github.com/blog/1506-closing-issues-via-pull-requests
 [PR#9966]:https://github.com/rapid7/metasploit-framework/pull/9966
 [pre-commit hook]:https://github.com/rapid7/metasploit-framework/blob/master/tools/dev/pre-commit-hook.rb
 [API]:https://rapid7.github.io/metasploit-framework/api
-[Module Documentation]:https://github.com/rapid7/metasploit-framework/wiki/Generating-Module-Documentation
+[module documentation]:https://github.com/rapid7/metasploit-framework/wiki/Module-Documentation
 [scripts]:https://github.com/rapid7/metasploit-framework/tree/master/scripts
 [RSpec]:http://rspec.info
 [Better Specs]:http://www.betterspecs.org/
 [YARD]:http://yardoc.org
 [Issues]:https://github.com/rapid7/metasploit-framework/issues
 [Metasploit Slack]:https://www.metasploit.com/slack
-[#metasploit on Freenode IRC]:http://webchat.freenode.net/?channels=%23metasploit&uio=d4
+[#metasploit on Freenode IRC]:http://webchat.freenode.net/?channels=%23metasploit&uio=d4