INT-2755: Support 'id' for <chain> sub-components

* Introduce XSD 'id' attribute for all `<chain>` sub-components
* Register `<chain>` sub-components as Beans with names based on `<chain>` 'id'
* Generate aliases for sub-components based on element 'id'
* Add `<chain>` parser test to check sub-components as Beans within `BeanFactory`
* Ignore `NestedChainParserTests` as abnormal and confused for SI-configs
* Now `<chain>` sub-components are trackable by `MessageHistory`
* Now `<chain>` sub-components are eligible for JMX export
* Polishing some failed tests

https://jira.springsource.org/browse/INT-2755
https://jira.springsource.org/browse/INT-2321