flent: Integrate flent-tools into the flent package

flent: Integrate flent-tools into the flent package

Now that we're packaging flent itself, there's no reason to have a
completely separate flent-tools package. So integrate the flent-tools
package specification into the main flent package so it's always kept in
sync.

Also add a dependency from flent itself on flent-tools, as the shell
versions of those utilities that Flent uses when running tests doesn't work
on the busybox shell included with openwrt.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>