Add Cache class for using WordPress built-in transients in more readable way

[onnimonni]

Hello!

I just love to use transients for almost everything in WordPress. It enhances loading speeds significantly. But I'm always frustrated how ugly it looks:

if (false === ( $resources = get_transient( 'my-resources' ) ) ) {
    $resources = Resource::all($start,$end);
    set_transient( 'my-resources', $resources );
}

I used anonymous functions to create Cache class so you could refactor upper code example into:

$resources = Cache::store('my-resources',function() {
    return Resource::all($start,$end);
});

This should be familiar for all javascript guys using herbert.
This also respects Pragma: no-cache headers from the request.

There might be better and more readable ways than this but I'm adding it here as a suggestion.

[jeremyzahner]

@onnimonni I guess you could manage merging this yourself? =)

[onnimonni]

I just didn't hear thoughts from anyone else. Does this look like something others would be interested as well?

[onnimonni]

@jasonagnew I know you're busy, but do you have opinions 😃?

[jeremyzahner]

@onnimonni I think it's great. What we (you) probably should do, is integrate such changes in a finished project done with Herbert to see if it is working as intended.

[onnimonni]

That's harder for me to do because the project where I used these is closed source and owned by my client. I can hopefully do unit tests instead.

[jeremyzahner]

@onnimonni Yeah, merging all kind of new functionality much quicker will become easier once we get proper unit tests for the framework.