lnd: change start/stop order of subsystems
lnd: change start/stop order of subsystems

This commit adds the part of the changes made in this PR:
https://github.com/lightningnetwork/lnd/pull/1783. The origin PR is
quite outdated, instead of rebasing it the relevant changes are taken
out and put into this commit.

aakselrod/lnd,aakselrod/lnd