Create math module

Renamed */maths.[ch] to */math/utilities.[ch]. Added license
statement for Sun FDLIBM. Uncrustified files in new module. Removed
orphan crecipdata.c file and invsqrt_test.c. Updated #include guards.
Moved some non-performance-sensitive function definitions from maths.h
to utilities.c.

A future patch will deal with vec.h.

Change-Id: I954cc48487c1af7f59f5a18c012c76d4297f7cab