GUI3D Populate ParticleDistribution using 3D container

Add checks to see if any particle is present inside ParticleComposition/ParticleCoreShell/ParticleDistribution

Add bool as second parameter to addParticle method and remove extra fillContainerParticlesBlend method

Functional tests for FitObjective

GUI3D ParticleComposition population from Particle3DContainer

Redmine issue 2081: revision of specular fitting examples

Use ParticleCoreShell as parameter for extending reusability of particleCoreShell3DContainer function

Use core Particle as parameter instead of ParticleItem for extending reusability of singleParticle3DContainer function

Returned back ancient "multi pattern fit" test for the sake of comparison with new FitObjective machinery

Redmine: #2081