Suggest and Schema Service Caching & Delay after metric keydown

Hi Abs,

I made a few tweaks in caching and metric suggestion. These hacks should shave off a lot of redundant connections to the server.

Delay in metric suggestion to reduce server load, delay is set at 1 second now.

Suggest and Schema Service Caching 
-Will cache result to prevent schema get to be called each time a metric suggestion happens.

Before: note that schema get is called each time suggestion made.
![screen shot 2014-08-13 at 2 56 58 pm](https://cloud.githubusercontent.com/assets/3792401/3913794/1b3e2bea-233c-11e4-9758-f1fdebd8e4c2.png)

After : only called once with the first suggestion
![screen shot 2014-08-13 at 3 48 51 pm](https://cloud.githubusercontent.com/assets/3792401/3913796/1f76161e-233c-11e4-8ab3-a90f1948bf5a.png)