Make scripts idempotent to avoid issues with redeployment

[lawrencegripper]

For example with Solr you will see The container name "/opencga-zookeeper-3.4 is already in use by container "1e50fa40deb7d8b938a89f233ae730ad323a0f08af5495a87612069e5e35a56e". You have to remove (or rename) that container to be able to reuse that name.

And with Azure Batch the pool won't be re-created so any updated config for the pool will be missed.

Todo:

• Fix solr deployment script Enable solr and zookeeper ARM template to be redeployed #995
• Remove workaround for Batch pool creation and use updated ARM API to create and manage the pool

[marrobi]

@lawrencegripper think should split this up - one issue per script?

[lawrencegripper]

I'm easy either way, feel like it could be done as 1 PR so keep 1 issue but not a strong feeling

[lawrencegripper]

Workaround removed for batch