Network now handles signal mixing, and does clamping. Test flight passes.

quad/computation_graph/src/computation_graph.c

quad/computation_graph/src/graph_blocks/node_accumulator.c

quad/computation_graph/src/graph_blocks/node_accumulator.h

quad/computation_graph/src/graph_blocks/node_add.c

quad/computation_graph/src/graph_blocks/node_add.h

quad/computation_graph/src/graph_blocks/node_constant.c

quad/computation_graph/src/graph_blocks/node_constant.h

quad/computation_graph/src/graph_blocks/node_gain.c

quad/computation_graph/src/graph_blocks/node_gain.h

quad/computation_graph/src/graph_blocks/node_mult.c

quad/computation_graph/src/graph_blocks/node_mult.h

quad/computation_graph/src/graph_blocks/node_pow.c

quad/computation_graph/src/graph_blocks/node_pow.h

quad/sw/modular_quad_pid/src/control_algorithm.c

quad/sw/modular_quad_pid/src/control_algorithm.h

quad/sw/modular_quad_pid/src/graph_blocks/node_bounds.h

quad/sw/modular_quad_pid/src/graph_blocks/node_constant.c

quad/sw/modular_quad_pid/src/graph_blocks/node_constant.c

quad/sw/modular_quad_pid/src/graph_blocks/node_constant.h

quad/sw/modular_quad_pid/src/graph_blocks/node_constant.h