Move pipeline loading to filebeat setup

[kvch]

Have

• Ingest pipelines are loaded right before messages are sent to ES.
• Pipelines are never updated by default.
• A yet unreleased flag --update-pipelines forces Filebeat to update pipelines

Wanted

• Have setup command load the pipelines.
• Pipelines are updated every time setup is called.
• When calling run, pipelines are loaded before messages are sent.
• Make --update-pipelines a config file option, so users do not have to edit their init scripts if they want to use this option or update the pipeline when e.g convert_timezone option has changed.