JBIDE-15398 CDI Builder is sloooow

Methods CDICoreNature.getAllAnnotations() and
DefinitionContext.getAnnotation(String)
are optimazed in case of many dependencies in workspace.

Existing tests for dependent projects must pass.
JBIDE-15385 Support annotation @Priority

Annotation @Priority is used to determine bean enablement
and to resolve ambiguous dependencies. Test is added.
JBIDE-15504 cdi spits out hundreds of exceptions if you have deleted a project in eclipse

Cleaned a cache of annotations from parent projects in DefinitionContext on
close, delete, or remove from classpath of a parent project.