[timeloop] ensure that end time is never exceeded

See merge request !1167

[common] Add function for generic interpolation

See merge request !1166

Fix/caching staggered

See merge request !1143

* empty cache filler used
* contains several todos
* fluxVarsCache not used anywehere, but might be required in future

* reference solution needs to be updated because test uses time-depended Dirichlet BC
* old behaviour was actually wrong

* directly creates elementSolution from CC privars

* only local element needs to be bound

* use bind instead of bindElement

Resolve "Cleanup of 2pnc and 2p2c models"

Closes #355

See merge request !1161

[freeflow][outflow BC] Introduce that there is no gradient normal to the outflow…

See merge request !1155

Melanie Lipp authored Jul 30, 2018 and Kilian Weishaupt committed Aug 03, 2018

[freeflow][outflow BC] Introduce that there is no gradient normal to the outflow boundary in cases where the outflow boundary is the normal face with respect to the assembled scvf.

[rans][problem] Make ctor accept modelParamGroup

See merge request !1165

[freeflow] Clean-up Fick's and Fourier's law

See merge request !1162

Fix/checkpoint timeloop

Closes #544 and #539

See merge request !1160