LinearSolve keyword arguments aren't applied to cache

[jClugstor]

In construct_linear_solve the linsolve_kwargs are being passed in to the LinearProblem, but aren't reflected in the cache. e.g. setting the reltol in linsolve_kwargs doesn't actually apply it to the cache. This can be fixed by just putting the kwargs... at the end of the call to init. May also be a bug in LinearSolve, because it should work either way.

I'll get an MWE etc. later, putting this here so I remember to document etc.