Updated git introduction page (#601)

* Updated git introduction

* added newline for linter

Author: bryanyli

source/docs/software/basic-programming/git-getting-started.rst

@@ -122,6 +122,8 @@ In the previous example, we created a file called README.md. Open that file in y
      1 file changed, 2 insertions(+), 0 deletions(-)
     > git push
 
+.. note:: Writing good commit messages is a key part of a maintainable project. A guide on writing commit messages can be found `here <https://chris.beams.io/posts/git-commit/>`_.
+
 Git Pull
 ^^^^^^^^
 
@@ -278,3 +280,5 @@ Additional Information
 ----------------------
 
 A much more in-depth tutorial can be found at the official `git <https://git-scm.com/docs/gittutorial>`__ website.
+
+A guide for correcting common mistakes can be found at the git `flight rules <https://github.com/k88hudson/git-flight-rules/blob/master/README.md>`_ repository.