Clarified comments in safety policy files

Signed-off-by: Andreas Maier <maiera@de.ibm.com>

.safety-policy-all.yml

@@ -1,6 +1,12 @@
-# Safety policy file
+# Safety policy file for packages needed for development.
 # For documentation, see https://docs.pyup.io/docs/safety-20-policy-file
 
+# Note: This policy file is used against the versions in minimum-constraints.txt
+# That file includes minimum-constraints-install.txt with '-c'. Since that is
+# not supported and ignored by the safety tool, this policy file ends up being
+# checked just against the minimum versions for development, without install.
+# That's ok since the 'install' safety profile checks the install packages.
+
 # Configuration for the 'safety check' command
 security:
 

.safety-policy-install.yml

@@ -1,6 +1,8 @@
 # Safety policy file for packages needed for installation
 # For documentation, see https://docs.pyup.io/docs/safety-20-policy-file
 
+# Note: This policy file is used against the versions in minimum-constraints-install.txt.
+
 # Configuration for the 'safety check' command
 security: