Initialize web resources validator + UI preferences. See
https://github.com/angelozerr/eclipse-wtp-webresources/issues/10
Fix https://github.com/angelozerr/eclipse-wtp-webresources/issues/12
Use IWebResourcesContext
Validate several class names + improve search performance
Fix https://github.com/angelozerr/eclipse-wtp-webresources/issues/16
Try to fix
https://github.com/angelozerr/eclipse-wtp-webresources/issues/17