FacetDataPlot and ParticleDataPlot TimeIntervall

[rwendner]

please allow for
"DeleteAllFiles",
"TimeIntervall" and
"TimeIntervallCurve" also in the MLDPM as well as the MFEM paraview plots.

This will help development and comparison between the mechanical strains in the standard plotlists and the MLDPM SVs.

Ideally, we have for all plotlists the RealTime and the ComputationalTimeIntervals, and respective Timecurves.

[zhouxinwei]

Suggestion will be considered.