Add FFT functions

Also add new size types to BKBase.h.
Implement BKComplexDiv
Rename normalization transform option
Add missing Makefile.am
Fix whitespace
Use inline functions instead of macros
Correct wrong division function
Add some functions
Rename functions
Cleanup code
Add C++ program macro
Rename FFT test program
Correct wrong logo

-.-"
Cleanup code
Add option parameter to sample loading function
Rename the complex type's fields

`real` -> `re`
`imag` -> `ìm`
Merge branch 'fft' into develop
Merge branch 'develop'