Change template names to rocky

The new master branch should point now to rocky.

So, HOT templates should specify that they might contain features
for rocky release [1]

Also, this submission updates the yaml validation to use only latest
heat_version alias. There are cases in which we will need to set
the version for specific templates i.e. mixed versions, so there
is added a variable to assign specific templates to specific heat_version
aliases, avoiding the introductions of error by bulk replacing the
the old version in new releases.

[1]: https://docs.openstack.org/heat/latest/template_guide/hot_spec.html#rocky
Change-Id: Ib17526d9cc453516d99d4659ee5fa51a5aa7fb4b

firstboot/conntectx3_streering.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 description: >
   This's a temporary workaround for adding this option

firstboot/os-net-config-mappings.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 description: >
   Configure os-net-config mappings for specific nodes

firstboot/userdata_default.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 description: >
   This is a default no-op template which provides empty user-data

firstboot/userdata_dev_rsync.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 description: >
   This is first boot configuration for development purposes. It allows

firstboot/userdata_example.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 # NOTE: You don't need to pass the parameter explicitly from the
 # parent template, it can be specified via the parameter_defaults

firstboot/userdata_heat_admin.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 parameters:
   # Can be overridden via parameter_defaults in the environment

firstboot/userdata_root_password.yaml

@@ -1,4 +1,4 @@
-heat_template_version: queens
+heat_template_version: rocky
 
 description: >
   Uses cloud-init to enable root logins and set the root password.