Monitored: Remove backwards compatible code

• remove C++14 backwards-compatible code
• remove deprecation warnings in defineHistogram
• improve unit tests

unmarked as a Work In Progress

changed the description

This merge request affects 1 package:

• Control/AthenaMonitoring

Adding @ssnyder ,@rbianchi as watchers

added Core DQ master review-pending-level-1 labels

CI Result SUCCESS

	Athena	AthSimulation
externals
cmake
make
required tests
optional tests

Full details available at NICOS MR-20897-2019-02-13-18-10
Athena: number of compilation errors 0, warnings 2
AthSimulation: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST 33729]

Seems fine, approving....

Pavol [as L2 MR shifter]

added review-approved label and removed review-pending-level-1 label

merged

mentioned in commit dd56d592

added sweep:ignore label