Implementing the feature request in BUG #385429.
https://bugs.kde.org/show_bug.cgi?id=385429
LookAndFeels introduced the ability to set dependencies, that are downloaded first before installing the look and feel package.
https://userbase.kde.org/Plasma/Create_a_Look_and_Feel_Package
Eg: X-KPackage-Dependencies=kns://plasmoids.knsrc/api.kde-look.org/1160672
It will call:
```
/usr/lib/x86_64-linux-gnu/libexec/kf5/kpackagehandlers/knshandler kns://plasmoids.knsrc/api.kde-look.org/1160672
```
Previously this file called `engine.install(entry);`
the second argument (`linkId`) isn't supplied so it defaults to 1.
```
void install(KNSCore::EntryInternal entry, int linkId = 1);
```
This means it downloads the first link, which for me is the oldest version of the widget typically.
https://api.kde-look.org/ocs/v1/content/download/1160672/1
tells it to download tiledmenu-v05-kde5.5.plasmoid
while
https://api.kde-look.org/ocs/v1/content/download/1160672/3
tells it to download the latest version tiledmenu-v18-kde5.9.plasmoid
This patch adds the ability to specify which link to download in the 3rd path section.
Eg: `kns://plasmoids.knsrc/api.kde-look.org/1160672/3`