add global http queue

[seiyria]

to avoid the client getting too throttled for some actions (rapid market clicking, hovering lots of notifications), the entire client should queue http requests and send them out every 100ms, rather than immediately upon calling the function.

this will require the following services to use this wrapper:

• gamplay.service
• fight.service
• leaderboard.service
• market.service
• notifications.service
• player.service
• user.service

Somehow, they'll need to return their observable to be subscribed to, while putting them in a queue. One potential library to use is https://www.npmjs.com/package/rx-queue#delayqueue.