LightSpeed: Improve caching to specify which url-parameters to accept

[iJungleboy]

I'm submitting a

[x] bug report => search github for a similar issue before submitting
[x] feature request

...about

[x] Lightspeed / performance

Current Behavior / Expected Behavior

Goal is to specify what url-parameters should be cache-relevant, to avoid cache growing to many possible value combinations.

Your environment

• 2sxc version(s): 17.09