Clarify that examples are using a default labels configuration

By reading the owners plugin documentation it looks like some
defaults are invarant, like the Code-Review label and its score.
However, when customising Gerrit default Code-Review label, the
behaviour may change radically depending on the changes made
and the owners plugin documentation would therefore become misleading.

It is an impossible task to document all the possible combinations
of the label settings and the implied behaviours on the owners plugin,
therefore just clarify the context of the examples so that the
reader would be advised on the underlying preconditions.

Change-Id: Iebe702b7956ba275140f882ac3bc0750cb5918fd
diff --git a/owners/src/main/resources/Documentation/config.md b/owners/src/main/resources/Documentation/config.md
index 1d157c6..debba42 100644
--- a/owners/src/main/resources/Documentation/config.md
+++ b/owners/src/main/resources/Documentation/config.md
@@ -148,7 +148,7 @@
 > configuration is used) so that owners don't have to be granted with the
 > maximum label's score. Note that only single digit (0..9) is allowed.
 
-For example, imagine the following tree:
+For example, imagine the following tree with a default Gerrit project labels configuration:
 
 ```
 /OWNERS
@@ -200,7 +200,7 @@
 - Doug Smith
 ```
 
-### When `owners.enableSubmitRequirement = true`
+### When `owners.enableSubmitRequirement = true` with a default Gerrit project labels configuration
 
 Then Gerrit would:
 
@@ -251,7 +251,7 @@
 - Doug Smith
 ```
 
-### When `owners.enableSubmitRequirement = true`
+### When `owners.enableSubmitRequirement = true` with a default Gerrit project labels configuration
 
 This case is supported with the `Code-Review` label and `OWNERS` file
 modifications.
@@ -336,7 +336,7 @@
      label-Owner-Approved = -1..+1 group Registered Users
 ```
 
-### When `owners.enableSubmitRequirement = true`
+### When `owners.enableSubmitRequirement = true` with a default Gerrit project labels configuration
 
 Given now an OWNERS configuration of:
 
@@ -386,7 +386,7 @@
 shouldn't be granted with `Code-Review +2` for all project files as it might be
 outside of their comptenence/comfort zone.
 
-### When `owners.enableSubmitRequirement = true`
+### When `owners.enableSubmitRequirement = true` with a default Gerrit project labels configuration
 
 Given an OWNERS configuration of:
 
@@ -427,7 +427,7 @@
   - Matt Designer
 ```
 
-### When `owners.enableSubmitRequirement = true`
+### When `owners.enableSubmitRequirement = true` with a default Gerrit project labels configuration
 
 Then for any change that contains files with .sql or .css extensions, besides
 to the default Gerrit submit rules, the extra constraints on the additional
@@ -461,7 +461,7 @@
 
 ## Example 6 - Owners details on a per-file basis
 
-### When `owners.enableSubmitRequirement = true`
+### When `owners.enableSubmitRequirement = true` with a default Gerrit project labels configuration
 
 This case is obsolete and _only_ prolog specific. The list of which file is
 owned by whom is available through the [REST API](rest-api.md).