runtime: exposing set_min_noutput_items to python.
digital: examples will fail without some Python packages but need sys module to exit properly.
Revert "volk: add regex option to profile"

This reverts commit 9b37687d6ebd89c6c582be233c5ddac1390b80ed.
digital: replaces buffer copies with fir_filter_with_buffer to handle more sanely and with fewer extra copies.