Updated config_yaml (markdown)

config_yaml.md

@@ -112,6 +112,81 @@ urls:
        tag: chris, customer
 ```
 
+### Tag Grouping
+New in v1.6.0 is Tag Grouping!  This allows you to assign a group to previous tags defined.
+```yaml
+# Define your Groups
+groups:
+   friends: user1, user2
+
+# Define your URLs
+urls:
+  # One-liner (no colon at the end); just the url as you'd expect it:
+  - mailto://credentials:
+      - tag: user1
+  - mailto://credentials:
+      - tag: user2
+```
+With respect to `Group Example #1` above, you could now send a notification to the tag `friends` and that would in turn trigger a notification to all of the URLs that were included indirectly to that tag.  In this case, `user1` and `user2` would be notified.
+
+Another great thing about groups is you can assign groups to groups to recursively include everything they're apart of:
+```yaml
+# Define your Groups
+groups:
+   finance: user1, user2
+   devteam: user3, user4
+
+   # Here we create another group and assign it groups
+   # We also can mix and max tags in line with group assignments too
+   # like so:
+   company: finance, devteam, boss
+
+# Define your URLs
+urls:
+  # One-liner (no colon at the end); just the url as you'd expect it:
+  - mailto://credentials:
+      - tag: user1
+  - mailto://credentials:
+      - tag: user2
+  - mailto://credentials:
+      - tag: user3
+  - mailto://credentials:
+      - tag: user4
+  - mailto://credentials:
+      - tag: boss
+```
+
+With respect to `Group Example #2` above, you could now send a notification to the tag `company` and that would in turn trigger a notification to everyone because they're all associated with the group tag.
+
+You can also assign tags to multiple groups:
+```yaml
+# Define your Groups
+groups:
+   # Multiple Group Assignments; reuse of a tag causes existing assignment
+   # to stack on the previous value.
+   TeamA, Friends: user1, user3
+   TeamB, Friends: user2, user4
+
+# Define your URLs
+urls:
+  # One-liner (no colon at the end); just the url as you'd expect it:
+  - mailto://credentials:
+      - tag: user1
+  - mailto://credentials:
+      - tag: user2
+  - mailto://credentials:
+      - tag: user3
+  - mailto://credentials:
+      - tag: user4
+```
+
+With respect to `Group Example #3` above, we have 3 group tags created (TeamA, TeamB, and Friends).  TeamA includes user1 and user3, and Team B contains user2 and user4.  The Friends tag actually includes user1, user2, user3, and user4 (all entries stacked).
+
+**Some Notes:**
+- There is no requirement to define the group before or after the URLs that are defined.
+- Tags associated with a group that are not used are just ignored.
+- Reuse of the same group assignment stacks it's values (it does not replace them)
+
 ## Expanding Configuration Sources
 The YAML based configuration also supports the keyword `include` which allows you to pull more configuration down from other locations. For example:
 ```yaml