Fix nothing to cache

[breakbuidl]

There was no check for nothing to cache if custom expiration < 0. This PR adds that check.

Also, the current implementation checks if expiration < 0 for nothing to cache. However nothing must be cached also in the case expiration = 0. Hence, improved the current implementation to expiration <= 0 for nothing to cache.

[ReneWerner87]

@breakbuidl can you check my review comments ?

[breakbuidl]

Hey @ReneWerner87, sorry for the late replay, just got back to this. Will finish this over the weekend.

[ReneWerner87]

@breakbuidl any progress on the weekend ?

[ReneWerner87]

@breakbuidl?

[gaby]

@breakbuidl Friendly bump

[ReneWerner87]

due to the non-activity, combined with the fact that we don't really see a case for it, because the expiration can't be less than 0 and even if it is, the entry isn't really cached then

so we close the pull request until the code is updated and/or the need is described in more detail