Additionally slightly refactor GlobalLinSys classes to avoid a circular shared_ptr dependency in AssemblyMap that caused segmentation faults in Python wrappers.

Add documentation to NektarCommon.cmake and remove ADD_NEKTAR_TEST_LENGTHY in deference to a LENGTHY option to ADD_NEKTAR_TEST

Fix libANN using file from other branch, replace OCC with v6.9, add ability to compile OCC from source

Switched Metis.hpp to call Scotch instead for partitioning.

Removed Git SHA1 and Branch from compile definitions on files except FieldIO.cpp