This updates the fluent-logging chart to support the creation of
an arbitrary number of templates for elasticsearch. This allows
for the definition of multiple index mappings driven via the
chart's values. This provides flexibility in determining specific
structures for indexes that may differ between log types.
This also moves to define these mappings via json instead of XML.
As gotpl can convert yaml directly to json, and elasticsearch can
ingest json directly for index creation, we no longer need an XML
helper function to generate the required configuration. This helps
reduce the number of helper functions we need to maintain
Change-Id: I3c85fb9a1e700eb1592d96f83e632172d0eb2681
4b8f46abee