cleanup high order

- don't die silently when a read function fails
- fixed while bunch of compiler warnings

- fixed missing getShapeFunction/getGradShapeFunction + return all sf
  at once so we can implement MElement in term of these consistently
  (w or w/o FunctionSpace)

- can now merge multiple meshes and remove duplicate mesh vertices
  (useful e.g. when merging several STLs)

- added easy interface to create model-based postpro datasets on the
  fly + use this for mesh quality stats

* removed unused stuff (more to come)
* moved remaining into Common

- log vector scaling (idea from bernhard Kubicek)

  did in high
* added mesh generation error log summary
* removed Parallel subdir (this is now handled by the message class)
* removed Box subdir and consolidated batch processing in a single
  routine
* made List_T into a class
* reduced dependencies in Pview*.h so we can eventually add the post-pro
  interface to the public API

better "make lib" (cannot simply merge static libs with ar on linux)

rewrote adaptive view stuff so we can use it on all types of views
(model-based, multi timestep, multi-mesh)