utils: use new control interface

Knot.files

doc/man/knot.conf.5in

doc/man/knotc.8in

doc/man_knotc.rst

doc/reference.rst

src/Makefile.am

src/knot/conf/scheme.c

src/knot/conf/scheme.h

src/knot/ctl/commands.c

src/knot/ctl/commands.h

src/knot/ctl/process.c

src/knot/ctl/process.h

src/knot/ctl/remote.c

src/knot/ctl/remote.h

src/utils/knotc/commands.c

src/utils/knotc/commands.h

src/utils/knotc/estimator.c

src/utils/knotc/estimator.h

src/utils/knotc/main.c

src/utils/knotc/remote.c