Basic concurrency support for available public methods

[onevcat]

No description provided.

[eschos24]

When is this going to be available in an upcoming release? Is there a reason it is going into v8 and was not part of 7.10?

[onevcat]

@eschos24
The related changes (and also some others) contain breaking changes to the current version, so it is planned to be a part of the upcoming version 8.0.0.

If you'd like to try it now, you can use the v8 branch as an early bird. (The most noticeable breaking change is that all the existing disk caches will be invalid since the cache key format is changed.)