fix: MySQL/Postgress max_idle_conn default was wrongly set to zero, which does not mean unlimited but zero, which in practice disables connection pooling, not good. now max idle conn is set to golang's default which is 2, fixes #8513

* graphite-ds: add graphite version to config editor

* graphite-ds: modify add-graphite-function to show only version-related functions

* graphite-ds: refactor, move func filtering to gfunc.js

* graphite-ds: add new functions for graphite 1.0.x

* graphite-ds: fix unit tests (add jsonData)

fixes #8989

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Reference document:
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ons/Reference/SafariWebContent/pinnedTabs/pinnedTabs.html

Fixes #8187

Fixes #8872. Use the automatic calculation by Flot to get the
number of decimal places for ticks on the y-axis rather than
the number of decimal places for the min value.