expose datapoint alert templates as tokens

Because the current template mechanism has no support for conditional statements, inclusion of other content or other similar features that would make it useful for operations, our plan is to feed all the tokens into our incident management tool and generate the correct output via an intermediate knowledgebase template filter.  The one thing we will miss here is the semantic content included in the various datapoint alert text -- it would be very helpful if this could be exposed as a token for use within integrations.  Also, it would be nice if the custom email integration supported an option to add custom headers and to format data as JSON or YAML.  I hopefully will end up with a REST method, but for now the data must be sent as email and it is impossible to send that data in a proper data structure now, just text.

Thanks,

Mark