Feature post release cleaning

Various code tidying up to use newer C++11 and 1706 features but would have been too late for the June code-freeze.

• FoamArch : combine from argList and regIOobject
• cleanup run-time selectables to use auto and cfind
• remove NamedEnum from loads of places.
• ABORT function object using a sub-list of Time stopAtControls enumeration
• degToRad() user literals and eliminate duplicate code
• streams :: name() - non-virtual
• MPI_BUFFER_SIZE, NAN, FPE setting via etc/controlDict, optionally via env-variables
• clamp handling for various tables (duplicate and untidy code)