Add guidlines for commit message (#24709)

* Add guidlines for commit message

Add sample .gitmessage with message template and update CONTRIBUTING.md
with setup and additional resources about commit templates.

references #24671, #24615, #21325

.github/CONTRIBUTING.md

@@ -92,13 +92,22 @@ http://www.stack.nl/~dimitri/doxygen/manual/faq.html
         $ git clone https://github.com/YOUR_USERNAME/Cataclysm-DDA.git
         # Clones your fork of the repository into the current directory in terminal
 
-3. Add this repository as a remote.
+3. Set commit message template.
+
+        $ git config --local commit.template .gitmessage
+
+4. Add this repository as a remote.
 
         $ cd Cataclysm-DDA
         # Changes the active directory in the prompt to the newly cloned "Cataclysm-DDA" directory
         $ git remote add -f upstream https://github.com/CleverRaven/Cataclysm-DDA.git
         # Assigns the original repository to a remote called "upstream"
 
+For further details about commit message guidelines please visit:
+- [codeinthehole.com](https://codeinthehole.com/tips/a-useful-template-for-commit-messages/)
+- [chris.beams.io](https://chris.beams.io/posts/git-commit/)
+- [help.github.com](https://help.github.com/articles/closing-issues-using-keywords/)
+
 #### Update your `master` branch
 
 1. Make sure you have your `master` branch checked out.

.gitmessage

@@ -0,0 +1,8 @@
+# If this commit is applied, it will ....
+# |<-- Using around 50, Maximum 72 Characters -->|
+
+# Explain why this change is being made
+# |<----      Limit Each Line to a Maximum Of 72 Characters       ---->|
+
+# Provide links or keys to any relevant tickets, articles or other resources
+# Example: fixes #1234, closes #2345, resolves #3456, references #4567