Fix/missing templated fields loki prometheus + log line value format for Loki

[Issif]

What type of PR is this?

Uncomment one (or more) /kind <> lines:

/kind bug

/kind cleanup

/kind design

/kind documentation

/kind failing-test

/kind feature

Any specific area of the project related to this PR?

Uncomment one (or more) /area <> lines:

/area build

/area config

/area outputs

/area tests

What this PR does / why we need it:

The templated fields were not included a labels in loki/prometheus outputs.

A new option for Loki to change the format of the value in the log lines: text or json.

Which issue(s) this PR fixes:

#1090

Fixes #

Special notes for your reviewer:

[poiana]

LGTM label has been added.

Git tree hash: fc567e4e5424e19c69c6f39678c6153fb4165497

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, Issif

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• OWNERS [Issif,cpanato]

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