treewide: upgrade ucitrack handling to use json

[feckert]

Maintainer: @stargieg @PolynomialDivision @wfleurant Compile tested: no Run tested: no

Description: This depends on pullrequest in the LuCI feed.

The ucitrack configuration under /etc/config defines which service must be restarted on a LuCI change. This uci file defines how all this works together. Additionally there are uci-defaults scripts in the various applications that add additional configurations parameters to this ucitrack file if a service must be reloaded/restarted if a uci change was made in this application.

There are some problems with the current implementation:

• The uci should be used to configure the system and not for this kind of reload/restart dependency handling on LuCI changes.
• On a system update with configuration restore of the uci file ucitrack the new behavior on LuCI reload/restart could not take into account because the new file is not be used.

[feckert]

The base PR has been merged. Since I have no commit rights for this feed. Can one of those @BKPepe @aparcar who have this merge this change?