Add recognition modes to the enrollment metadata

This will be used by the Voice interaction service to determine what type of recognition may be run
on the DSP. e.g. If the DSP supports voice trigger only for the given keyphrase,
the voice interaction service may want to perform user identification at its end.

Also support keyphrase metadata for all keyphrases and locales.
In case the enrollment app supports open-ended keyphrases, it can leave the keyphrase text
to be empty
similarly, if the enrollment app supports all locales, it can leave the supported locales
attribute to be empty,

Change-Id: I782a17a877fc79ed569fa7c3a81697641182590b