* $__timeFrom() -> Returns the dashboard 'from' suitable for use querying
against a MySQL TIMESTAMP field.
* $__timeTo() -> Returns the dashboard 'to' suitable for use querying
against a MySQL TIMESTAMP field.
* $__unixEpochFiler(column) -> If you store timestamps as UNIX epoch's,
this builds: column > 'from' AND column < 'to'
* $__unixEpochFrom() -> Returns the dashboard 'from' suitable for use querying
against a MySQL integer field (UNIX epochs)
* $__unixEpochTo() -> Returns the dashboard 'to' suitable for use querying
against a MySQL integer field (UNIX epochs)
* Fix timeInterval for mysql datasource
This changes the > to >= and the < to <=, so the intervals are inclusive.
This should fix the #8635
* Fix validation