Docs: Run Output - Clarification and Additions

Clarification of the meanings of and the distinction between the
output-related terms iteration, job, workload and section for those
unfamiliar
- Add entries to the glossary and references to the glossary
- Added section on Configuration parameter hierarchy
- Added section on the number and names of directories generated for
jobs in the run output folder

doc/source/user_information/user_reference/configuration.rst

@@ -21,7 +21,9 @@ if it does not already exist. This file must always exist and will always be
 loaded. You can add to or override the contents of that file on invocation of
 Workload Automation by specifying an additional configuration file using
 ``--config`` option. Variables with specific names  will be picked up by the
-framework and used to modify the behaviour of Workload automation.
+framework and used to modify the behaviour of Workload automation e.g.
+the ``iterations`` variable might be specified to tell WA how many times to run
+each workload.
 
 ---------------------
 
@@ -97,3 +99,9 @@ it is not possible to know the end users intention and WA will error.
 This functionality allows for defaults for plugins, targets etc. to be
 configured at a global level and then seamless overridden without the need to
 remove the high level configuration.
+
+Dependent on specificity, configuration parameters from different sources will
+have different inherent priorities. Within an agenda, the configuration in
+"workload" entries wil be more specific than "sections" entries, which in turn
+are more specific than parameters in the "config" entry.
+