Pass configured/auth headers to a Datasource.

In some setups (ex openshift), the Datasource will require Grafana
to pass oauth token as header when sending queries.
Also, this PR allow to send any header which is something
Grafana currently does not support.

Conditionally select a field to return in ResponseParser for InfluxDB

Fix error in InfluxDB query

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build: fix signing of multiple rpm packages

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https://github.com/grafana/grafana-docker/issues/170
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Make sure to process panels in collapsed rows when exporting dashboard

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graph: fix legend decimals precision calculation

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Fix dashboard drop down links

Fix regressions after save modal changes

expose session and transaction helpers to other services

Fix problem with adhoc variable filters not handled.
Fix problem with saving variables and time per default when saving a
dashboard as/first time.
Fix updating dashboard model after save with saving time/variables
enabled so that next time you save you won't get checkboxes for save
time/variables unless any values changed.
Tests validating correctness if time/variable values has changed.

* Karma to Jest: history_srv

* Fix TS errors

* Remove q, as it is not needed

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ldap: allow use of DN in group_search_filter_user_attribute and member_of

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* Begin Karma to Jest: time_srv

* Remove experimental fix

* location search stubs for each test

* Fix issue where time service was not available for other tests

Minor error in sql query to retrieve annotations

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#11607 Cleanup time of temporary files is now configurable

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