Fix #727 : The user should be able to set the timezone used in scenes in the UI

[Pierre-Gilles]

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Description of change

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[codecov]

Codecov Report

Merging #856 into master will increase coverage by 0.00%.
The diff coverage is 95.83%.

@@           Coverage Diff           @@
##           master     #856   +/-   ##
=======================================
  Coverage   93.49%   93.49%           
=======================================
  Files         428      428           
  Lines        5578     5595   +17     
=======================================
+ Hits         5215     5231   +16     
- Misses        363      364    +1     

Impacted Files	Coverage Δ
.../services/philips-hue/lib/light/light.getLights.js	97.14% <ø> (ø)
server/utils/constants.js	100.00% <ø> (ø)
server/lib/variable/variable.setValue.js	90.00% <83.33%> (-10.00%)	⬇️
server/lib/index.js	94.28% <100.00%> (ø)
server/lib/room/room.getBySelector.js	100.00% <100.00%> (ø)
server/lib/scene/index.js	100.00% <100.00%> (ø)
server/lib/scene/scene.addScene.js	94.44% <100.00%> (+0.10%)	⬆️
server/lib/scene/scene.init.js	100.00% <100.00%> (ø)
server/lib/variable/index.js	100.00% <100.00%> (ø)

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