Improve performance by specifying a larger size for the UI Templates cache

The cache labelled "UI Templates" (cache:com.atlassian.confluence.util.ConfluenceVelocityResourceCache) currently has the size of 100. Changing the size of the cache on CAC to 300 showed the increase in the effectiveness of the cache and overall confluence performance. Having the bigger size cache in this case decreases the number of time we need to go through the resource loading code. In resin app server resource loading is very slow and avoiding it improves the performance.

We should increase the cache size to 300 in our cache configuration. It would be very beneficial for any app server:

        <local-scheme>
            <scheme-name>cache:com.atlassian.confluence.util.ConfluenceVelocityResourceCache</scheme-name>
            <scheme-ref>default</scheme-ref>
            <high-units>300</high-units>
            <expiry-delay>1800s</expiry-delay>
        </local-scheme>