New parameter `infinispan_jgroups_cluster_nodes` to explicitly set initial nodes

[guidograzioli]

When infinispan_jgroups_discovery is TCPPING, the cluster initial node list is pre-configured automatically using the hostvars included in the ansible_play_hosts. This new parameter allows to override the behaviour, explicitly setting all needed jgroups parameters.

Variable	Description	Default
infinispan_jgroups_cluster_nodes	List of node definitions for jgroups cluster, read below for the format	[]

The infinispan_jgroups_cluster_nodes parameter, when empty, tell the collection to geenrate the list from the hosts variables in ansible_play_hosts; otherwise, it can be passed-in using the following dictionary format:

infinispan_jgroups_cluster_nodes:
  - address: 10.0.0.175
    inventory_host: '10.0.0.175[7800]'
    name: us-east-2-datagrid-1
    port: 7800
    site: us-east-2
    value: 'tcp://10.0.0.175:7800'
  - address: 10.0.0.179
    inventory_host: "10.0.0.179[7800]"
    name: us-east-2-datagrid-2
    port: 7800
    site: us-east-2
    value: 'tcp://10.0.0.179:7800'

where address, port, and inventory_host are connection details; name is the name of the host in the cluster, site is the name of the cluster in the xsite configuration, and value is explicit connection string.