Improves web-service performance.

This allows various rather static responses to be cached, substantially
lightening server load and improving page response time.
Added test for etag filter
Lowered log level
Merge branch 'beta' of github.com:intermine/intermine into cachier-models

Conflicts:
	intermine/web/main/src/org/intermine/web/filters/ReleaseEtagFilter.java
Merge pull request #669 from alexkalderimis/cachier-models

Improves web-service performance.