Add gist reference in README, fix title

README.md

@@ -6,3 +6,7 @@ Get Python packages backends found in `pyproject.toml` files with the
 This could be done thanks to [Querying every file in every release on the Python Package Index](https://sethmlarson.dev/security-developer-in-residence-weekly-report-18)
 from Seth Michael Larson.
 
+The `pyproject-sqlite-get-files-and-extract-backend.py` script makes use of
+Seth Michael Larson gist : [pycodeorg.py](https://gist.github.com/sethmlarson/852341a9b7899eda7d22d8c362c0a095)
+
+

plot-packaging-backends.py

@@ -32,13 +32,14 @@ if __name__ == "__main__":
 
     cnx.close()
 
-    fig = plt.figure(num=f'{backends_total} backends used in pyproject.toml on PyPI (2018-2023)', figsize=(12,8))
+    fig = plt.figure(num='Backends on PyPI', figsize=(12,8))
     ax = fig.add_subplot(1, 1, 1)
 
     bars = ax.bar(backends, backend_nb, color=['blue' if n > 500 else 'cyan' for n in backend_nb])
 
+    ax.set_title(f'{backends_total} backends declared in pyproject.toml on PyPI (2018-2023)')
     ax.set_xlabel("Backend")
-    ax.set_ylabel("Times used")
+    ax.set_ylabel("Times declared")
     
     """ 
     TODO : .../plot-packaging-backends.py:62: