COMMON: Add asserts

These asserts are preventing in-place processing.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Add peak finding-related common functions

These may be used in order to find the parabolic estimated minimum of a
given data buffer.
Part of #5.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
DESCRIPTORS: Add AFF sources

Fixes #5.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
MANAGER: Make AFF an available descriptor.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
MANAGER: Minor helper comment

Signed-off-by: Gama <misept.dieseneuf@gmail.com>