Assets caching tweaks

Primary purpose of this changeset is to add CB value to all Resource Loader requests. This allows us to have consistent JS code on the edge between Assets Manager and Resource Loader. This hit us a bit during past few releases.

Second small tweak is to unify cache TTL of all assets that we serve through apaches, now Assets Manager uses Resource Loader's configuration. This means we're slightly changing caching TTLs in AM in the following way:
- AM requests coming with newer CB value than one present in the code - will be cached for 5 minutes instead of 10 minutes,
- AM requests with CB value equal or lower than one present in the code - will be cached for 1 month instead of 1 week.

This is also a preparation part for tweaking assets caching TTL. Since RL cache configuration has two separate values for client and server, this will allow us to significantly decrease caching time at client side at the application level if we decide so.

@Wyvek @macbre @owend your comments are welcome, I hope to get it reviewed and merged today so it goes out with next week's release