Use static_size_fft for small transforms larger than vec_size too.
Added BitReverse.bit_reverse_static_size.
Removed fft_tiny.
Added @always_inline to two functions.
Merge branch 'static-size-for-vectors' into multidim

Conflicts:
	build.d
	pfft/common.d
	pfft/fft_impl.d
Fixed some errors.