Change EntitySpec from interface to DTO

- And deprecates BasicEntitySpec, WrapppingEntitySpec and EntitySpecs
Convert usage of BasicEntitySpec/EntitySpecs to EntitySpec
Merge branch 'refactor/EntitySpecs-to-EntitySpec' of https://github.com/aledsage/brooklyn

Conflicts:
	core/src/main/java/brooklyn/entity/basic/ApplicationBuilder.java
	software/nosql/src/test/java/brooklyn/entity/nosql/redis/RedisIntegrationTest.java

(tiny conflicts due to var names changed near uses of new EntitySpec.create)