Refactor Science.cpp to split functions into separate files.
=== Science === The directory Science/ now contains files corresponding to the various functions in the now-removed Science.cpp.
Filenames correspond directly with the function name, and each file contains only one functions, with a few notable exceptions.
- Science/get_quads.cpp contains get_quads_x, get_quads_y, and get_quads_z
- Science/compute_background_PE contains the helper function compare_pairs
The global variables _quadw_x, _quadw_y, and _quadw_z are declared as extern in Science.hpp and declared in Science/compute_quadweights.cpp
=== Makefile === The Makefile has been modified accordingly. It now automatically detects all Science/*.cpp files and includes them in the compile recipe.
The Makefile has also been tidied up a little bit by defining a variable SPINS_BASE which points to the core files.